Calli's First Word (we think)

Well, we think Calli has said her first word. She's been babbling for ages and is now in love with going "dadadadadada". We didn't think much of it other than that she was babbling. Lana thought it was hysterical and kept saying "No, Calli. Daddy's at work." But she looked right at Brent when he got home and said "Dada" or maybe even "Daddy" for sure. Later before baths, she looked at him again and said "hey daddy" or some version there of twice. So I guess she says Dada now (and knows what it means...and uses it for a lot of other things too). Why do my girls always start with "Dada"? Lana and I are working on "Mama" now. :-) I'll post a video of Calli babbling "dadadadadada" when I have more energy but it's late and I have to be up early tomorrow for school and work.