Michael Strahan is embracing being a grandpa, but doesn’t exactly want to be called one.

The Good Morning America co-anchor—who became a first-time grandparent when his eldest daughter Tanita Strahan gave birth to baby boy Onyx Sept. 22—revealed why he doesn’t want to use the traditional moniker as he steps into his new role.

“It’s the most amazing feeling ‘cause I don’t feel old enough,” the 52-year-old told Jimmy Fallon during an appearance on The Tonight Show Sept. 23. “Everyone’s like, ‘What is he gonna call you?’ I don’t know. I almost want to do a survey.”

When the late-night host proposed he go by “Papa,” Strahan suggested adopting the name “Gap-pa,” in a nod to his trademark gapped teeth.

While Michael tests the waters on the moniker, he’s enjoying this new chapter with his family.

“I’m so happy for my daughter Tanita and Calenta [Mincey], her boyfriend,” the former NFL star gushed, adding that baby Onyx is a “great addition to the family.”

Michael—who shares Tanita, 32, and son Michael Strahan Jr., 31, with ex-wife Wanda Hutchins as well as 19-year-old twins Isabella Strahan and Sophia Strahan with ex-wife Jean Muggli—revealed the news of the new arrival on the Sept. 22 Fox NFL Sunday broadcast.

“It’s really special because I know you guys have gone through this,” he told his co-hosts, all of whom are grandfathers. “Now I'm just happy to be able to join you in that club.”

The TV host has spoken about his children, including Tanita, on occasion.

“She’s kind of like me in the sense that she has a very strong personality, but a silent strong personality,” he told New York Family in 2013. “She’s not going to be one to walk into a room and make it all about her. She definitely has an opinion and she’s very smart and she knows what she wants, which I love about her.”

As for Isabella, who shared her brain cancer diagnosis in January, Michael has praised her strength throughout her treatment journey, calling her “superwoman” in an Instagram post in June as she finished her final round of chemotherapy.

“You continue to fight with a smile on your face, strength, and determination,” he wrote of his daughter, who is now cancer-free. “I am one proud Dad!”

For the latest breaking news updates, click here to download the E! News App