Hi i wouldn't worry too much, i have 1 son and 3 daughters, my son was the same and he used to just grunt at everything up until the age of 20mths then he started talking a few words as he was getting frustrated, my eldest daughter was late talking as well she just babbled like your son but her own babble until the age of 2 then she actually talked in sentences all at once. Then my middle daughter i had concerns with and still do as she didn't babble at all just sat and watched everything and everyone, until the age of 2 and half then her first word was gog, dog at 2 and half, she had not speech therapy as i believed my partner that she had brothers and sisters talking for her, she is now 6 and still quite lazy in her speech and she is also behind in her school work. Just keep an eye on him, i have an 18mth daughter and she is totally different she can talk quite a bit mum, dad, ben, shouts disa for lisa, go, there it is, all gone, bye, hi sings beginning of rhymes, points to eye, ears, nose mouth, belly and bum so she is fairly forward so they are all different, just keep an eye on him and if you are still worried at all just take him back, my middle daughter was still hard to understand at age 3 and half. Yes boys are not as quick as girls, girls are ready for gossip, lol. Sharon x
and when my eldest son ended up talking it was in a complete sentence.
He was later identified in the gifted area of IQ- graduated college and is a psychologist'
try not to worry