So what happens next?

[stopgap]

DS1 is 2.8. He used the potty once about four months ago, freaked out, so we abandoned ship.

But yesterday morning he took off his wet nappy and decided that he wanted to use the potty. So we had no nappy in the afternoon, and he peed and pooped in it once. Great.

Today he was without a nappy for two hours in the morning, and two hours after his nap, and yet, nothing. He sat on the potty for half an hour during both nappy-less periods, and did not go, but nor did he have any accidents.

What do I do next? Just more of the same encouragement and timely intervention, with pull-ups for his afternoon nap (2.5/3 hours long) and bedtime?

I'd carry on as you are, it sounds like you are off to a good start.

I'll explain what I'm doing now, which had a similar start to you 4 months ago (we even went shopping for big girl pants) but she wasn't interested.

I think we need a support group as I am making this up as I go along It sounds like a good start. This is what we did / are doing with dd who is (2.8):

Brought some ladders for the toilet. They have novelty, she feels safer on them too.

Talked about "no more nappies" 5 days ago, and each day.

Talked about her collecting stars for one treat present at the end of the week. Reward chart is simple one I made - sun to sat, space for stars to stick on.

On Sunday, didn't put a nappy on. Reward chart ready, star given for going in toilet initially, then for weeing on it. She got 4 stars sun, 7 on Monday and so far on 6 today.

She is telling me when she needs a wee, and still asking for her nappy when she needs a wee, but we are just taking her straight to toilet and saying no nappies. She is panicking a bit, but I've kept calm and not made a fuss of the 1 accident she's had.

Today she had a 2 hour nap, no nappy and was dry. We put her straight on toilet when she woke up and she did a big wee.

Does this help?