‘The Big Bang Theory’ Star Johnny Galecki and 21-Year-Old Girlfriend Alaina Meyer Expecting First Child

Johnny Galecki is taking on a brand new role: Father of one.

As the actor gets ready to say goodbye to his role as Leonard on CBS’ hit comedy series The Big Bang Theory, the 43-year-old announced he and girlfriend Alaina Meyer are expecting their first child together.

“We are absolutely over the moon to announce that we will soon be welcoming a little one into this crazy and wonderful world,” the couple confirmed in a statement to PEOPLE.

“We ask that you please respect our privacy during this celebratory time for us and our families. There truly is love out there for all. We hope ours is the ember of yours, as we feel yours is the ember of ours,” Galecki and Meyer, 21, added.

The couple were first romantically linked in public in September 2018, making their awards show red carpet debut at the E! People’s Choice Awards 2018 in Santa Monica.

The pair’s relationship has blossomed quickly, as they have frequently been on vacations with Meyer’s family and they both regularly gush about one another on social media.

“I’m feeling so grateful after our family vacation,” Meyer wrote on the caption of a black-and-white of the pair with some of her family after a vacation in March. “We made memories that will last a lifetime and we were surrounded by such genuine, loving people the whole time. I’m filled up with love and gratitude for the people in my life and the lessons we encounter to grow closer to our highest selves.”

Meyer also made headlines throughout filming of Big Bang‘s final season, as she frequently visited the set to keep her boyfriend company. The series filmed its series finale last week. The couple has also attended several awards shows together, and have hung out with some of Galecki’s closest friends including his The Conners co-star Sara Gilbert. They also frequently go on vacations and appear to be working on music together, as seen on Meyer’s Instagram.

Back in December, the couple faced their first set of engagement rumors among fans, which was brought after Galecki posted a photo of the two of them wearing matching rings.

“I see matching rings,” said one Instagram user, while another commented, “Are you married???”

Meyer shut down the rumors at the time by posting the same photo, adding the caption: “#notmarried.”

The Big Bang Theory two-part series finale will air Thursday, May 16 at 8 p.m. ET on CBS.