Unlike Sky, the character he plays in Mamma Mia, Adam Jacobs comes from a close-knit family — so close, in fact, that all the members share the same musical gene and itch to entertain.

Jacobs’ grandmother was a cabaret singer who was asked by Tommy Dorsey to travel with his band at the ripe age of 15. Jacobs’ mom always sang in the choir at church, and his little sister Gabrielle began her entertainment career at age 6, performing with song and dance troop Razzle Dazzle in California. When Gabrielle invited Jacobs to start voice lessons and join her, he jumped at the chance. They performed in hotels and at weddings for years, before Jacobs discovered community theater.

After that, he decided to attend the musical theater program at New York University’s Tisch School of the Arts. It was then Gabrielle’s turn to follow, attending a performing arts high school and then the Steinhardt School of Music at NYU. “We never had much sibling rivalry,” Jacobs says. “We supported each other.”

It was only natural, then, that Jacobs would marry into an acting family. He met his wife Kelly while performing at a Christmas show in Hershey, Penn. “I was Santa and she was a rag doll,” he says. “She went to Tokyo for seven months to perform at Disney there, and I flew out twice to visit. We got married three years ago.”

Kelly is now touring with Mary Poppins. With both Jacobs and Kelly on the road, maintaining the relationship can be difficult, but they make it work. “We have an arrangement where we make it possible to see each other once every three weeks,” he says. “If we go longer than that, [we] get really agitated on the phone and that sort of thing.”

In between visits, the couple uses cell phones, Skype and Webcams to keep in touch. At the beginning of a tour, they lay out their schedules side by side with an atlas and see where and when visits make the most sense. “The most important thing is knowing when the next time we are going to see each other is,” Jacobs says. “We like to plan ahead.” It helps that he is able to negotiate extra vacation time, and that Kelly’s tour usually has three or four days in between stops.

In lieu of having each other, they do have their “show” families. “On the road, you bond and hang out because all you have is each other,” Jacobs says. “You really make lasting friendships on tours.”

Another side benefit of doing theater is it keeps Jacobs in shape. For Mamma Mia, he had to put on 20 pounds of muscle for the role of Sky — and he’s not getting any complaints from Kelly about it! She’s come to see the show 10 times, and he goes to watch her act, sing and dance, as well. “We give each other notes if we think it’ll help,” he says. “We have no qualms about that. There’s no competition [in our relationship]. If anything, it helps [to be in the same industry] because the other person knows what it’s like and understands the traveling and the [need] to be away a lot.”

Next up for Jacobs and Kelly? Children. “We just bought a house in Sunnyside, Queens [N.Y.] and there’s a room that could be a baby room, eventually,” he says. “After these tours, the best thing would be for Kelly to get into the Mary Poppins Broadway company. And, [if] I could get on a Broadway show, we could both be in New York. [But,] we’ll just take it all as it comes.”

Mamma Mia plays at the Fox Theatre Feb. 9-14.