What should be the diet of a 14 mth old?

my little daughter is just about to complete her 14 mths.and weighs 10.82 kgs.According to the doctor she is doing aerage in her weight....and this is after when,I push her for eating.....But,my mother in law is after my life and says me to feed her less so that she should'nt put on more weight and become fat in her growing years....let me tell you honestly,she is a very bad eater if left alone (hence,I run behind her with spoon)....she will keep ping comments of how much i feed her and what should I feed her....she insisted me on feeding her 'low fat yoghurt and also dosent let me mix biscuits with her milk,something which is so normal for babies!....and keeps arguing with me to feed her less so that she shouldnt get over weight,in future huh!!! not only this but my father in law (who himself is a doctor) also keeps an eye on how much i feed her and why i keep running behind her for food and all....i really dont understand when,I am the mother and if i want my child to eat well what is their problem...and the worst part is i cant tell them anything....I really dont know how to explain her things!I feel so frustrated!please help....i explained their behavior to my husband who sees us during the weekends and he strictly told me he can't raise a voice against his parents inspite of the fact that he loves his daughter....kindly help,please....what should I do? :((((