Well, not exactly, according to Ms. Sullivan, an artist who now lives in Vienna, Va. In her version of events, she had been plotting to set the wheels in motion for years, from the first time she met Mr. McKay.

“With Andy, it’s what you see is what you get,” she said. His honesty and straightforwardness seemed well suited to her sister. But Ms. Sanford’s social calendar didn’t allow for a long-distance setup, at least not at first. “Jenny had been dating and I wasn’t crazy about the people she was dating,” Ms. Sullivan said. “I knew it was going to take a special kind of person to make her happy.

“We all know the story of Jenny and Mark,” she continued, adding that she is still close with her former brother-in-law. “I wanted her to experience what it was like to have someone love you unconditionally. I don’t think she had ever experienced that.”

She was sure Mr. McKay, who had been divorced since 2013, could deliver. “He’s mellow, he’s very intelligent, he’s a family man, and he’s trustworthy,” she said. As for the 600 miles separating them, she convinced Mr. McKay that traversing the distance would be good for him. “I was seriously bullying him,” she said. “I told him, ‘Who are you going to meet in Louisville? You’ve already met everybody. You’re not going to find your person here.’”