DS has pretty much only ever said "da" when speaking. Babbles nonsensical sounds all the time but when pointing and trying to communicate anything, it's literally just "da" for everything. No attempt to copy the sound of a word, but will mimic the syllables (will say "da" in response to ball, or "dada" in response to penguin, for example). No other concerns. Amazing comprehension, can understand and follow multi task instructions and has been able to for months (can you get a ball and bring it to mummy). I keep saying he'll have a sudden explosion of vocabulary but the fact he still doesn't even say mama is beginning to worry me. Not saying 3 different words (dada, mama and baba for example) was the only thing he couldn't do during his 1 year check so the HV was really happy with overall development as he was ahead in other areas.