If the Christmas spirit is about family, Craig Robinson and Michelle Obama are its brother-sister embodiment.

“I’d spend a lifetime admiring him for his ease,” the former Michelle Robinson wrote in her new memoir, “Becoming Michelle Obama.”

The 412-page best seller that has sold more than 3 million copies is filled with odes to the Knicks’ vice president of player development.

The former first lady touts her brother’s “optimistic spirit,” calling him “my protector since the day I was born” who “made me laugh more than any other person on Earth.”

“True, I am here to entertain her,” Craig Robinson told The Post in a rare interview.

Robinson, 56, didn’t help his sister write those passages, but spent several hours across two days last January in her Washington apartment “brainstorming” over old stories such as “boxing matches in the kitchen.” And even more hours over the phone.

Robinson said their bond, growing up in a small apartment in the South Side of Chicago, was so tight as kids that their parents felt he was overprotective.

“We were always close because we were close in age, two years,” Robinson said. “My parents never made it that, ‘It’s OK, she can’t do this because she’s a girl.’ She played sports with me, rode bikes with me. She got to do everything I got to do. We were friends and playmates growing up. To the point my mom said, ‘You got to stop worrying about your sister. She can do stuff on her own.’ I would make sure she was included or taken care of before I can start enjoying myself.”

This is the man Knicks president Steve Mills hired in August 2017 to oversee the franchise’s player development, the NBA’s newest rage. Signing free agents from other clubs is more arduous than ever. As a result, building through the draft and extracting the most out of the current roster has become paramount.

Robinson is the third-most influential voice of the Knicks’ front office, after Mills and general manager Scott Perry. Robinson, a former head coach at Brown and Oregon State, is in charge of nurturing the baby Knicks as he nurtured his baby sister, Michelle, who recalls in the memoir how he staged elaborate fire drills in the house to ensure family safety.

Mills played alongside Robinson at Princeton, where Michelle followed her brother’s footsteps as a student.

“We still talk all the time,” Robinson said. “She wants to know how things are going and how I like my job. She’s not going to say, ‘Hey, you guys should change the lineup.’ Barack tells her what’s going on. I can’t tell you how many games Barack is watching, but he’s paying attention to the Knicks.”

Michelle is no longer a basketball diehard. The 6-foot-6 Robinson attributes it to his sister watching too many of his games across her childhood.

“She had grown not to like it because she got dragged to so many different basketball games,” Robinson said. “She never played. Part of the reason she didn’t play, it wasn’t the same attention paid to women’s basketball. She could’ve been a really good player. But she came to the games at Princeton because everyone was going. If everyone wasn’t going and I wasn’t playing, she wouldn’t have gone.”

One of the telling anecdotes of Michelle’s trust in her brother came when she was mulling whether to marry the future president, who had just graduated from Harvard law school. Michelle asked her brother to invite Barack, as a test, to one of his pickup games.

“Craig’s opinion of Barack mattered to me and my brother knew how to read people, especially in the context of a game,” Michelle wrote.

“He’s no ball hog,” Craig said, according to the memoir. “But he’s got guts.”

Robinson explained further.

“She always heard my dad and I say, ‘You can always tell a person’s character by how they play pickup basketball,’ ” he said. “When she started getting serious with him, she said, ‘Hey, could you take him to play with the guys you play with?’ She said, ‘I’d really love to hear your input on this.’ ”

After the game, Robinson gave Michelle a positive scouting report.

“I realized he wasn’t selfish,” Robinson said. “He wasn’t greedy. He showed character on the court. He called fouls and gave up fouls. You have to trust the guys you’re playing with in pickup, they’ll make the right call. He did all of that. I was able to get back to her and say, ‘He seems like a pretty good guy.’ The best thing about it I told her is he didn’t just pass me the ball because he was dating my sister.”

So does Robinson believe he clinched the marriage?

“I don’t think I clinched it, but I moved it in the right direction,” said Robinson, who walked Michelle down the aisle because their father had recently passed away at age 55. “I might’ve been able to derail it, but they had to clinch it.”

Robinson was on hand when Michelle first introduced Barack to their parents. According to the book, Robinson and his father were on the stoop watching Barack leave that fateful evening. The father blurted to his son, “Nice guy. Too bad he won’t last.”

Robinson agreed then with the sentiment.

“My sister hadn’t dated anyone she didn’t go to Princeton with for more than two months,” Robinson said. “He seemed like a nice guy, but in a month and half, she’ll be on to the next one. It was more accurate than tongue-in-cheek.”

Robinson has attended two of the stops along Michelle’s book arena tour.

“It’s unimaginable sitting in a packed arena, set up like a concert, seats on the floor,” he said. “People are sitting there as she tells her stories. It just amazes me.”

Barack Obama is also working on a final memoir. The famous couple, according to Robinson, have a bet on which book sells more copies.

“If I were her husband,” Robinson said, “I wouldn’t be competing with her.”