In the rafters at Madison Square Garden hangs a banner in honor of Billy Joel, who holds the record in that hallowed arena for the most performances by an artist. Seated under that banner were Alex Steen and Jaden Schwartz, teammates on the visiting St. Louis Blues, who were playing the New York Rangers.

At one point during their game, Schwartz motioned to the Billy Joel banner and directed Steen's attention there. "Hey," he asked Steen, earnestly, "did that guy play for the Rangers or something?"

Steen didn't just laugh -- he guffawed. It was one of those jokes that landed so well it became legendary, a character detail affixed to Schwartz in perpetuity:

How funny is Jaden Schwartz? Well, did you hear about the Billy Joel banner thing?

Schwartz, 25, has vacillated on the intentions of that joke, at one point having claimed to not know Billy Joel from Joel Ward to now saying that the aim of his punch line was true. "No, I was just bugging Steener. Wanted to get a giggle out of him. Gotta keep the guys loose," he said.

Humor being one of our most subjective forms of human interaction, the Blues have many theories about Jaden Schwartz's particular brand of whimsy.

"Honestly? I'll say this as well as I can: He's dumb-funny," said Darren Pang, a former NHL goalie and a color commentator for Fox Sports Midwest. "I don't know if he means it half the time. I don't know if he was actually asking if Billy Joel played for the Rangers when he saw that banner. He just says some things where you shake your head and wonder, 'Did he really mean to ask that as a question?'"

That "dumb-funny" was also on display when Schwartz reads the starting lineups in the Blues locker room, a responsibility given to him by former St. Louis defenseman Kevin Shattenkirk.

"I still provided a lot of the material for him. A bit of a ghostwriter. Getting him to read sometimes ... we weren't actually sure if he could read or not," quipped Shattenkirk, who is now with the Rangers. "He has his moments where he'll say something, and you just remember that he's from Wilcox, Saskatchewan."

(Apologies to the good people of Wilcox, Saskatchewan, population 399.)

"He's one of those guys where you laugh at his expense. But he's a great guy and a phenomenal teammate," said Shattenkirk.

Jokes aside, the Blues consider Schwartz to be an endearing soul and a hard-working talent -- one who also happens to rank fourth in NHL scoring this season. On and off the ice, he consistently brings them joy.

"Guys want to be around guys like that. Where on the ice, they're in the zone and wanting to win, and then off the ice, it's all about the joke or the laugh. He's all about that," said Brayden Schenn, his friend and linemate.

There's plenty of joy around Jaden Schwartz. But it's balanced out by the considerable pain he has experienced.

Not a day has passed since Jaden Schwartz's sister's death that he doesn't think of her.

"Yeah," said Schwartz, quietly. "It's still tough."

Mandi was, like her younger brothers, Jaden and Rylan, a hockey player. She starred at Athol Murray College of Notre Dame in Wilcox, where she was the captain. She was accepted to Yale and excelled on its women's hockey team. But in late 2008, during her junior season, Schwartz began feeling significantly fatigued. Her team noticed something off about her game, as well. The catalyst for these symptoms stunned her and her family: acute myeloid leukemia. She left Yale and began treatment.

Before she was diagnosed with acute myeloid leukemia during her junior year at Yale, Mandi Schwartz was a star on the ice. Bone marrow drives on campus did not find a match for Schwartz but have generated 28 other matches for patients since. John Dunn/Icon SMI

A desire to return to hockey inspired her to battle the disease, and Mandi spent 5½ months in the hospital. In 2009, it was announced that her cancer was in remission, and she returned to Yale and the team's practices. Her journey back to the ice had inspired hundreds of students, who joined bone marrow-awareness drives on campus in her honor to broaden the registry. Social media had caught on to her fight, as well, with Facebook campaigns supporting national initiatives in her name.

"It was amazing how many people -- the football team, the hockey team -- signed up for the bone marrow registry. How many people were supporting me," Mandi said in January 2010.

Her cancer returned that April. In September 2010, she received a stem-cell transplant, and hope returned that she could overcome the illness. But a December 2010 biopsy revealed it had returned again.

That news came two days after Jaden -- then a freshman and the leading scorer for Colorado College, where Rylan was a teammate -- was named to Team Canada for the 2011 World Junior Hockey Championship. Jaden had been drafted 14th overall by the Blues in June 2010, and his burgeoning career was something that provided his older sister some happiness during her cancer treatments.

"This was her dream -- for me to make this team; she's as proud as anybody anytime I get an achievement or an accomplishment in hockey," Jaden told the Montreal Gazette in 2010. "Everything I do is for her. She's a hockey player, and she can't play hockey right now, so I'm kind of doing everything I can for her right now."

Mandi Schwartz died on April 3, 2011. She was 23.

Less than a year later, Jaden would play his first game with the Blues. His new teammates, like so many in the hockey world, were aware of the tragedy in his life. They opened their arms to him -- even if he wasn't always receptive to it.

"That was tough," recalled Shattenkirk. "Jaden's a guy who keeps his emotions to himself in that respect. He doesn't let it bleed into the team. At the time, a few guys would grab him aside and say, 'Hey, if you need anyone to talk to, we're all friends here.' It brought us all closer together, trying to support him in any way we could. You deal with something like this in your own way. His parents are always in St. Louis, always cheering him on. We feel like we're a part of that family now."

That was never more evident than in January 2014, when the Blues attended the "White Out For Mandi" fundraiser at Yale, a night when everyone in attendance wears white in support of the Mandi Schwartz Foundation. The organization works to honor Mandi's life and raise awareness about leukemia and becoming a bone marrow donor.

Not some Blues. All of the Blues.

"The Yale thing was really special," said Shattenkirk. "I know it meant a lot to them."

Jaden remains awed by the outpouring. "It's huge. It's something that we never expected to go through, but it's something you can't get through without the support of others," he said. "It's been like that ever since it happened, and it's important to us. It's kind of crazy to think about the impact she had on people."

That impact continues, through tributes and fundraisers. Such as at "Run For Mandi" in Saskatoon last August, a 5K that raised funds for stem-cell research and marrow donors. It was an event Jaden could attend because it was during the offseason. It was a chance to share the unfortunate education his family received on the need for more bone marrow donors, as Mandi never found an ideal match.

"I didn't know much about it. You don't know about it if you haven't had that situation before. So, obviously, I learned from it and realized how important it is to get the word out about it," said Jaden. "Some of my friends and their families weren't aware of what they could do to help. It's unfortunate that you have to put yourself in that situation, but the awareness is getting bigger and bigger."

Every event like this offers a chance to honor Mandi's memory. She lives on in the movement. And she lives on in her brother, playing out a hockey dream that meant so much to his sister.

Jaden Schwartz has 10 goals and 14 assists in his first 19 games this season for the Blues, skating with offensive star Vladimir Tarasenko and Schenn, his new center.

Well, new in their time with the Blues. But Schwartz and Schenn go back a long ways.

"When I got traded here, I texted him right away," said Schenn, who was acquired from the Philadelphia Flyers in June for center Jori Lehtera, the No. 27 pick in the 2017 draft and a conditional pick in the 2018 draft. "We've known each other since we were 10 years old, even though we lived about three hours away from each other in Saskatchewan. Playing against him in Philly, I knew how good he was. But once I came here, I got to see how hard he works on the ice. He's as good defensively as he is offensively. Hounds the puck, looks for turnovers and then goes on the attack. He goes all-out."

Pang refers to that style of play as being an "old-school thief" in the NHL.

"He can go into the corner and stop on a dime and get away from you, and yet he has the puck on his stick. You look at him and think that he's not that big, but he's hockey-big. It's like how Mike Babcock will say that a guy has a 'good lower half, a good lower half,'" said Pang, offering an impressive impersonation of the Toronto Maple Leafs coach, "and it's because he's coached Henrik Zetterberg and Pavel Datsyuk and guys who have those low, strong legs and rear end. And that's kind of what Schwartz is. He's not going to run you in the boards, but he's going to lift your stick and take the puck. If you watch Jaden very closely, he doesn't take many penalties, but he strips you of the puck."

"[Schwartz] is one of those guys who might be overshadowed by [Vladimir Tarasenko, left], but he's the Nicklas Backstrom to Vladdy's [Alex] Ovechkin," said Kevin Shattenkirk, not pictured, who has played with all four. AP Photo/Jeff Roberson

Schwartz said that he developed this style through the years, but especially in the NHL, where his 5-foot-10, 190-pound frame won't physically bludgeon opposing puck carriers.

"Growing up, I was always a smaller guy. I had to find ways to win puck battles," he said. "When you're on your toes, you can create a lot of offense by checking pucks back in the offensive zone and catching guys unexpectedly. I don't know if there's a way to explain it. I started doing it more when I got here, to be effective. There were guys in the league who I watched, like Zach Parise and Pavel Datsyuk, trying to pick up on the way they played and what they did."

So is he Datsyuk-like?

"A poor man's Datsyuk," said Schwartz. "Very poor."

Schwartz has 234 points in 336 career games since his debut in 2011-12, but the pertinent number here is 336: Schwartz has missed chunks of time during his career to injury, no more than in 2015-16, when a fractured left ankle reduced his season to 33 games.

The recovery from that injury lasted into the following summer and had an impact on the season after that, as well. Screws were inserted and removed from his ankle. Even through his rehab for the injury, it hurt like hell.

"Coming back and playing from that is tough," he said. "You can't do any leg workouts, you can't keep your legs in shape. Other parts of your body take a hit, as well."

Pang said this was evident on the ice. "His game is stops and starts, and escaping trouble. So he was getting hit a little bit more because he wasn't that quick," he said. "This year, he came to camp and he just looked more free because he's healthier."

Healthier, perhaps, than he's been in years.

"The last two or three seasons, he's always seemed to have some kind of injury that's happened to stop a hot streak, or just some sort of nagging injury. It seems like this year is the first year he's started off on a healthy body. He's one of those guys who might be overshadowed by Vladdy, but he's the Nicklas Backstrom to Vladdy's [Alex] Ovechkin," said Shattenkirk, in reference to the Capitals' dynamic duo with whom he played last season.

Schwartz's offensive explosion couldn't have come at a better time for the Blues, who opened the season with a bevy of injuries, including the loss of 21-year-old offensive whiz Robby Fabbri for the season because of a knee injury. Schwartz's start wasn't just solid from a personal-numbers standpoint, but essential from a leadership perspective.

"As you get a little bit older, you want to take a bigger step. You want to keep building offensively, but there are other parts of your game that are just as important, that lead to your offense -- your awareness, the way you move your feet, stripping pucks," he said. "I don't think about scoring a goal or getting an assist. For me, when you're thinking about that, I find I'm not working as hard as I need to.

"The offense takes care of itself when you do the little things in the game."

The little things matter. A joke that breaks up the dressing room, or the bench. A goal created when many felt the Blues were destined for an early-season, offensively deficient stumble.

Or a gesture, small as it is, that signals how a brother remembers his late sister, and her impact on his life.

"When Jaden switched from No. 9 to No. 17, when Vladimir Sobotka went to the KHL [in 2014], he quickly jumped on Mandi's number. He didn't do it with any fanfare, he just wanted to do it," recalled Pang.

"He's a special kid."