BW, Firstly, don't compare him, I know it's hard, but it is unfair to compare children (even if they are of similar gestations ect). Also try not to read into it much either, Sam might be excelling in other areas so therefore putting more effort into that.
By 18 months they want 50 'words' (they don't need to know the meaning of though) and some basic understanding. How is Sam's understanding? Thats the most important part, if he's got the undertsanding the speech will come. Also remember that our 'words' are usually different to theirs, for instance Brendan says 'dues' and thats his word for 'sore' or 'hurt' lol.
If you are concerned though speak to your CHN (they can refer you to the Speech Therapists if needed) I've found in my own experience that they won't focus on speech so much until after 18 months, unless there is another factor involved. For instance Brendan has being seeing ST's from 9-10 months old due to Tongue-Tie and the inability to eat properly.
If you like I can pass on some tips from our group sessions with Brendan's ST's. Send me a PM if your interested and I'll type out the phamplets, they may help in the meantime while you decide what you want to do or for the speech appointment ect.
Good Luck!
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