My fiance and I would love for his best friend's (who is the best man) little daughter to be our flower girl. The girl's father is divorced from the girl's mother and although he said he is delighted that we'd want his daughter as our flower girl, I am worried about his ex-wife. She is kinda crazy and doesn't like my fiance, so I am worried that if it would be her week to have the daughter, she would at first agree to switch weeks with him and then at the last minute take it back. Should I personally call her and ask, or should I just let the best man deal with her? Any suggestions as to how to deal with her?