My 2.5 year old DD has very abruptly started stammering significantly. She has always been a good and fluent talker with no issues. It seems really bad to me, she does it at the beginning of sentences and sometimes on bigger words like elephant. The only thing it coincides with is potty training- she's done really well with this though and has never been told off although she gets a bit worked up about doing poos. Really worried about what I could have done to cause this and why she would do this so suddenly.