DS2 is 7 months now and doesn't babble atall
When he makes noise it's just one continuous "aahhhh" he kind of hums when he's upset or he blows raspberries and that's about all the noise he makes (except crying obvs!)
My 5 year old had a speech delay so isn't comparable and I can't really remember how old the 6 year old was but I'm fairly certain he was starting to make "mamamam" "bababab" kind of noises by now
My friend has a baby just over a month older who says a couple of different words and can even say "how big" 
I know that's fast but it's got me thinking, should DS be saying more by now?