I'm in the same boat 35 weeks utd and my DS was 2 in July.

We've been using the toilet, after naps and before his bath etc but we are definitely still in nappies! I ask him if he want to go to the toilet and in the last few days he's been telling me he wants to go. I find he asks just after he's done a wee/poo in his nappy do he's not quite there yet.

A friend's little girl stopped using the toilet when the new bub arrived so I'm not getting too gung ho about it in case he regressed iykwim.

So no real help from me, just some solidarity