thanks ladies, i think i will have a chat to him when he gets back from work.
i understand the MIL is prob excited after all my DP is her only child, and this will be the first grandchild, and i am really appreciative they have brought so much for the little man. i think i will grab her over the weekend and just explain about the DPs ex girlfriend, she has her heart in the right place and maybe she thought it was a ok thing to do... thanks for easing me thru it ladies, muchly appreciated.