I would be annoyed also... My MIL Cant keep a secret either when it came time for my baby shower i cant tell you how many times she almost slipped so i would tell DH and he would yell at her it got to the point that i tried to avoid her and she did the same that way she wouldnt give it away!!!!!! My DH told her that when something is a surprise that she will find out the day before that way there is no way that she can mess it up... sometimes i think that they do it by accident but sometimes i think its done on purpose !!!!