DS is 18 months and understands and responds to whatever we say. However he only says 3 words I think, and probably noone else would understand them except us.
I dont think there is any problem with his understanding as we recently started baby signing with him as he seemed to be having a bit of a slow start talking and he has quickly picked up about 15 signs which he can use (if he remembers to).
My other children spoke well over 100 words very clearly by the age of 24 months, so only going by this I think DS may be a significantly delayed? Or do they come on really quickly when they ar ready?? I cant remember!!
My DS is 22 months and doesn't have many more than that. The last time I saw the HV they didn't seem worried but have referred him for a hearing test just in case. They all develop at very different rates.
DS is 20 months and is saying lots of words now (albeit a lot of them are ones that other people wouldn't understand) but his speech has come on pretty suddenly over the last 4-5 weeks. Before that, he was barely saying anything and then it was like someone flicked a switch and he's probably come out with 10 new words a day in the last few weeks.
So, what my waffle probably means, is that I wouldn't be too worried yet. 6 months (i.e. 18 month to 24 months) is a huge amount of time in your DS's life and he may well be saying 100+ words by that point, just like your other dc's
I think DS2 had about 5 words at 23 months and I panicked as I remembered DS1 being almost chatty with the health visitor at his 2 year check up. I would literally try to list on my fingers the words he could say. By 25 months he was talking in sentences, I like to think that he was waiting until he could do things properly . My friends beautiful girl has just turned two with a handful of words and now learns at least 10 a day or so it seems. 18 months is still proper baby, there is plenty of time.
My HV said they 'expect' or look for 5 words at the age of 2.
Once he starts he may pick it up quickly. My 20 month old wasn't early to start talking, but since he really got going, he learns on average 3-5 new words every day and has kept that rate of learning for a few months now. I know 3 other children the same age IRL who don't have a single recognisable word yet - I think that's normal too.
As Tillyscoutmum says, 6 months is a really long time in the life of a toddler.