There is so much more the OP could be focusing on right now but instead he is focusing on his 9 year olds belly over hang and preparing for another war with her over weight mother and her over weight family. Nice. Pity he didn't think about that when he was climbing in to bed with her.
He should be looking for ways to make sure his dd is settled in her new circumstances.
He should be looking for ways to rebuild his relationship and earn her trust as I've no doubt she is fully aware of the court battles.
He should be finding out what his child needs from him emotionally.
He should be making sure that is daughter is actually OK and how she feels about this all.
The kick back to the suggestion of fruit is ridged. No child ever got fat by eating too much fruit.
This man wants to put his 9 year old on a strict diet and start a new war with his ex the moment this court case was over. He just isn't done fighting yet.
The WORST place to come is on MN for diet advice as you literally have people living of half a piece of celery and two carrot sticks all day. A banana is a much better filler than a packet pf crisps as even if they have the same amount of calories the nutritional value is completely different - plus its more bloody filling.
OP if your still reading - the only person that will be damaged in this continual war you want to keep burning is your dd. You can't control what other her mother feeds her. Please do not fuck your dds self esteem up by letting her know you think she is fat. Get some REAL pediatrician diet advice that her you AND her mother can look at as a way forward.