"There's something about laughter and the longevity of a marriage," Bob Newhart said

Bob Newhart is opening up about the secret to his long-lasting marriage with his wife Ginny.

Sitting down with CBS Sunday Morning on Sunday, the 91-year-old comedian and actor revealed that laughter is the key to his 57-year-long marriage.

"There's something about laughter and the longevity of a marriage," Newhart told Ben Mankiewicz.

Today, Newhart and Ginny, who wed in 1963, have four children — sons Robert and Timothy, and daughters Jennifer and Courtney  — as well as 10 grandchildren.

Bob Newhart and wife Virginia
Bob Newhart, Ginny Newhart
| Credit: Courtesy Bob Newhart

Last year, Newhart opened up to PEOPLE and revealed that he has Buddy Hackett to thank for introducing him to his wife, as the late comedian and actor set the two up on a blind date.

"Well, we're both Catholic. She's three-quarters Irish. I’m three-quarters Irish," Newhart said. "Buddy said, 'I've got a girl for you. She's going with another guy, but I don't think he's right for her, so I'm going to fix you up on a blind date. You'll meet her and you'll date and you'll get married. Then you'll have kids and you'll call one of the kids Buddy.'"

"Which we did — one of our daughters, we called her Buddy,” Newhart joked.

Ginny, whose father Bill Quinn was an American film actor, has been there for all of Newhart’s successes over the years — and the occasional miss, which he also acknowledged at the time.

"She'd be in the dressing room. She'd say, 'Something's wrong with the sound system. I couldn’t hear anything,'" he recalled. "I said, 'Honey, nothing was wrong with the sound system. They didn’t laugh!'"

Bob Newhart
Bob Newhart
| Credit: CBS Sunday Morning

Elsewhere during his chat with CBS Sunday Morning, the Elf actor opened up about his illustrious career, which, like his love story with Ginny, has also been long-lasting.

Asked by Mankiewicz if he was still performing up until the ongoing coronavirus pandemic struck, Newhart shared, "Yeah, it's a narcotic!"

"People would say, 'Why do you still do it?'" he continued.

"I say, 'Yeah, you're right, I'm tired of making people laugh. I hate it,' " he joked.

Newhart added: "I have a theory that when it's all over ... and you go up — [if] I've been led to believe to heaven — and there's a God and he says, 'What did you do?' [And] I say, 'I made people laugh,' [He will say,] 'Yeah, get in that real short line over there.' "