Hi, my five and a half year old daughter has always been very tall. She's now in age 8 clothes in order to get enough growing room. She's always been right on the edge of being a healthy weight for her height so we've never really worried about what she eats. She does eat a lot. Her diet is fairly limmited but fairly healthy, just high in fat. She likes rice cakes with penut butter. My husband says she'll eat 6 of these for lunch. (I wouldn't let her eat that many, I'd offer an alternative after 2). My husband tends to just give her whatever she asks for though. She also likes cheese, toast, bread sticks and homous, baked beens etc. I've recently been giving her Rocs organic squash as I've heared that artificial sweetner is bad for them. She won't drink water and dosn't like her fruit juce diluted. 
Recently though, she's put on quite a bit more weight. She is now overweight for her height.
I'm wondering wether it's the change of drink that's done it or a combination of everything. She does have ice creams, popcorn, sweets or some form of a treat every day, sometimes several times a day if she's being looked after by my MIL.
I've talked to my husband about our daughters weight gain and he thinks it'd be cruel to put her on a diet saying "She loves her food", and "She's not that overweight". I know that everyone has to be supportive, because if they keep feeding her what ever her heart desires when I'm at work, then it'll become a real battle. I'm not going to let her go hungry, she'll just eat more fruit and vedge and I'll swap her white bread to granary, because she dosn't mind it, and change her drinks to sugar free. She will be a lot more healthy for the change, but some how I do feel a bit guilty for doing it. It somehow seems wrong to put a young child on a diet. She can still have the odd ice cream etc, but it'll be once a week instead of every day.
I think I'm doing the right thing as she dosn't want to walk as far as she used to, she was always such a good walker but now she says her knees hurt. (I'm not sure if this is true or not)
If anyone has some tips, I'd be greatful or ways of helping my family to understand why I'm doing this and to back me up. 