Baby doing well with motor skills but not language

So my baby just turned 7 months. As far as motor skills, she has been crawling, pulling up and sitting up since a little before 6 months.. so we are good there but she just is not a babbler. She never really did the back and forth chitter chatter and laughs but not an extreme amount. She does smile. She had a week before she started crawling where she did a few two consonant babbles but then completely stopped. this week we started doing mamas over and over but no other sounds. And it's never like a conversation just spuratic. Anybody have this going on?