Ideas for toilet training regression

[blushingmare]

My DS is 2.7 and potty trained over the summer (early I know, but he got half way there himself with running around naked and copying a friend using the potty on holiday, so I just carried it on once we got home). He's done so well and since September has been very reliable and no problems really.

Now, in the past month he has gradually regressed. He still wears a nappy at night and it started with he was waking up and doing a poo first thing in the morning before I got to him. That started with every now and then and gradually became a regular thing. Then he started having a few wee accidents here and there. And now over the past 4 days he has pooed in his pants several times.

I'm not sure what's going on or why he's doing it. Why would he go from being fully in control to virtually no control? And I don't know how to react - I never get cross with him, but I do tell him it's not the right thing to do and he should do it on the toilet - I guess my tone is a bit exasperated in the past few days too! He always says "sorry Mummy" and when I say "do them in the toilet next time", he's very enthusiastic, but then the same thing happens.

I've started this afternoon giving him incentives again (stampers on hand) for getting anything in the loo. But beyond this I really don't know what to do.

Any advice anyone?