Ok I am going to try hard to just stick to the facts here and not project about other stuff which may or may not be related.....
Dd1 is 3.6 and has been out of nappies since about 3.2. She did not get it straight away but has mostly been ok. Wee accidents are very, very unusual though they are still happening. Poo accidents are more likely and I reckon they are happening (being v honest with myself) about once a week.
I suspect tiredness is a factor - is this likely? Today for example we have been out since 10am, met a friend for a birthday thing in a cafe then we went to the aquarium for a mooch around and lunch. Dd1 has been distracted all day by her friends, soft play, fish etc and yet managed to tell me she needed the loo every single time! This included a poo and she is always praised. We got home about 4 and I just went in the kitchen to put the kettle on and when I came back she had had both in her pants! I am furious but also very confused as to why this is happening? Today is a good example of when we are having problems. Is it tiredness? Is it normal to regress a bit now and then?
I'm so frustrated as her behaviour in general has been excellent lately (not that she was particularly bad) and she gas been such a joy to spend time with that the loo problems seem so odd relatively 
Do I news to worry or is this normal?