Is your 6/7mo babbling with consonants? My LO will by 7mo this weekend, and while she has used consonants here and there (goo, bo, etc.), it's still rare. Lots of squeals and vowels, and laughs, but that's mostly it.
At this age my first kid was saying Dada, Baba, etc. sounds. She's 2 and is an exceptional speaker, so I don't expect my baby to necessarily be advanced like DD#1 is, but is she slow??
What are your 6/7mos doing in terms of vocalizing?