Leave room for surprises. Three months before their wedding, Cassandra Warren and Jesse Jones experienced a rather unexpected plot twist within their planning journey–and it was for a very sweet reason.

While Warren rapidly sent invitations to the couple’s growing guest list in March, she had accidentally mixed up a few details while addressing her aunt and uncle, who lived just 20 minutes away. What ensued was a series of events that would end with a heartwarming gesture from a stranger, who instead received the invitation.

“I was trying to get the invitations addressed while at work with a little one who was sick,” Warren, a nanny based in Eugene, Oregon, tells The Knot. “So she was on my lap while watching Finding Dory. [Meanwhile,] I was attempting to fill out all of the invites while watching Dory as well. It just so happened that I used an old address for my aunt and uncle. It was on the same street so I didn’t think to double check it was the correct address. “

One week later, Warren received that particular invitation back, with a handwritten note scrawled on the outside of the return envelope.

“My first reaction was that I was kinda annoyed my fiancé was more worried about who it came from and what it was instead of listening to me talk about work stuff that I needed him to help me with,” she says. “Then when he opened it, I just felt so blessed that someone would take the time to send it back… It helped my stress level and put some things into prospective.”

The note was a kind sentiment from a complete stranger, but more than that, it arrived at just the right time. “I wish I knew you—this is going to be a blast,” the note read. “Congratulations—go have dinner on me. I’ve been married for 40 years—it gets better with age.”

Inside the envelope was a $20 bill; scribbled elsewhere on the envelope was the phrase, “Live long and prosper,” perhaps a nod to the Star Wars and Harry Potter symbols Warren and Jones, 23, had included on their invitation.

The pair used the $20 toward their bill for a dinner out the next night with a friend who was set to be deployed overseas with the military. They then shared their story with the Washington Post, prompting the tale to go viral this week.

Warren and Jones, who have been dating for just over two years, are excited to get hitched in June. Jones proposed last Independence Day before both sides of the family right before the fireworks began. “I am personally just excited to do life with Jesse and see what life has in store for us,” Warren says. “We have been through a lot together already and I can’t wait to see what else we will go through, both good and bad.”

The pair will have several random “fandom” elements as part of their ceremony to showcase their personalities and interests, including chocolate frogs from Harry Potter as wedding favors and a Star Wars garter that says “May the force be with you” on it. The soon-to-be newlyweds even plan to walk back down the aisle to the “Death March” from Star Wars after exchanging vows.

As for the anonymous, wise would-be guest who sent Warren and Jones well wishes and money for a fun dinner out, Warren made sure that she knew how much her words had meant.

She says she bought a thank-you note and sent it to the same erroneous home, this time addressed to “Kind Stranger.”

“Thank you for the note and taking the time to send it,” she wrote. “Not many people would have done that. It was a big blessing after the day I was having. I am thankful for people like you still being in the world.”

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