DS (4 yrs) won't use potty or loo...

[Annabel7]

My son is has delayed development - low tone, delayed speech and young for his age, generally. Because of this, we've left it late to try and potty train. So far, he'll sit on the potty but not on the toilet and has NEVER weed or pood in the potty. His speech has come along to the point where he could tell me if he needs to go (but never does) and understands the process.

I read that kids with low muscle tone should go straight to pants so they can feel the wetness which, hopefully, helps them learn the cues and spurs them on to use the toilet but so far no luck. I'm not sure he knows when he is wee-ing.

I think the best thing, given the above, is to just take him to to the potty regularly. However, he won't go. I've tried to make it fun and also to bribe him but he went wouldn't go at all yesterday. I've now run out of clean pants so he's back in pull-ups.

I will post this in special needs also but wanted to ask generally for tips on how to: a) get him to use the potty; and b) get him to actually wee or poo in it.

Any ideas...?