Thanks for your replies.

She does actually ask to go to the toilet to do a poo but it's like she gets stage fright once she is on. I have tried moving the potty to a more private location as she does tend to go and hide when she does her poo's, but she just brings it back out. Pooing in a nappy gets her just as upset...she actually poo'd in her nappy tonight after we got her ready for bed and she started to cry because she didn't poo in the potty. We were just relieved that she had poo'd at all!! As a general rule though she won't do anything in her nappy anymore...for example we were at swimming lessons and she wanted to go to the toilet so we said just go in the nappy and she said no she wanted to go to the toilet. Will discuss all ideas with DH though...we don't want this to be a stressful time for her (another baby due in 6 weeks is going to be stressful enough!). Thanks again.