It’s a girl for Scooby-Doo stars Freddie Prinze Jr, and Sarah Michelle Gellar!

Freddie and Sarah welcomed their first child – a daughter named Charlotte Grace Prinze — on Sat., Sept. 19, a rep for the former Buffy The Vampire Slayer star told PEOPLE on Tuesday

It is the first child for the couple, who first met in 1997 while filming I Know What You Did Last Summer. They wed in 2002. Freddie and Sarah — who recently changed her surname to Gellar — are said to be “over the moon” about their daughter’s birth.