Parenting and the "clean your plate"/dessert mentality

Tiggermummy

My eldest daughter's eating habits have led to me changing some of what we do at home.

she was breast fed and baby led weaning, she eats pretty much anything, since starting nursery she has started the i don't like this.
she is very small for her age so she does need 5 meals a day otherwise she very quickly slips into the underweight for age/height senario, so gp has recommended giving her extra to keep her above the line. (she had extra large tonsils & adinoids removed before she was 3!)
I am very worried about teaching her bad habbits so we add cream or cheese to the meals where we can mix it in, without her knowing its there. We also put a lot less on her plate than we did, as we found if we put too much on it at the start she wouldn't eat anything. So she gets half a portion of whatever we are having and then once she has eaten all of that, then we consider a second helping or pudding ( which is mostly jelly or fresh/ tinned fruit). They only really have a snack tea weekday evenings as they have a cooked dinner at school and a tea there as well, it's too late for them to have dinner by the time we get home.
Her younger sister is small for her age but heavier (2 years younger) by a lb or 2, she again eats really well and the only thing she won't eat is fresh tomatoes as she knows she can't as they cause an alergic reaction!
We only have a few rules -
if it is something you don't like (like me & eldest with peas, hubby with sweetcorn) you have one desert spoonful of it.
We never have chocolate before lunch. ( we still have easter eggs from 2010, havent started the 2011 ones yet!)
and pudding is not automatic everynight.

It can be so difficult we have a nephew a year older that gobbles sweets and chocolate all the time if he can, and the girls see it.
I had to fight the whole family as I refused to let either of the girls have chocolate before they were a year old as they didn't need it!
we do try and resist the finish your plate insistance, both hubby and I were from the generation where it was expected, and I can remember being given my dinner the following night because I hadn't eaten it all.
Sometimes if we don't think she has tried as she just gets distracted we will divide up the food and find an ammount that we feel would be acceptable.