Macforme i think its very encouraging to hear that your son has found his voice. Im hoping that perhaps DS5 will eventually - he too (like phoenix DS) uses a bit of makaton really well, but is non-veral ATM. Interesting you say that your DS lost TA, my son too lost the 4words he learned (do-di {soother}, bird, daddy, and another i cant remember) and he could sign them at around 12mths too. But by 16mths he had lost them, signing, pointing, waving, and the understanding too ). I do remember tho he didnt really babble and wasnt interested in the 'chatting' that most parents and babies do.
Can i ask, did they ever find a reason for your DS's learning difficulties?
DS5 too is a 'baby', he is tiny (still in 12-18mth clothes even tho hes 3 next month, his understanding is probably around 12-18mths at a guess, theres not a chance of him understanding instructions/requests in school by september.
Its wierd, we were shopping the other day for DS4's birthday presents: a vtech camera, a hotwheels carwash and garage... meanwhile DS5's birthday next month we're looking at: cause/effect toys, rolling ball toys, basically toys aimed at 12mth babies... its wierd to think theres actually only 1yr 3wks between them.
We have just started the whole statementing process, he will be going to a MS nursery, as its a brilliant one, but i think its a 'wait and see' after that.