Am I a bad sister? What should I do?

[HappyChip]

Your younger sister is clearly very unhappy and is locked in a vicious circle of eating to make herself feel better and then becoming more upset because of the weight gain and so eating to comfort herself.

But you need to leave her alone. You are making things much worse. It is not your job to tell your sister to lose weight. I don't think you'd recognise sensitivity if it was served to you on a plate with a sprig of parsley on top. You say yourself that you consider your sister to be [another] "brain dead teen". Hark at you pontificating with your prediction of her being obese and unemployable after she leaves school! For goodness' sake, back off. You are not qualified to make a diagnosis of obesity. Your sister's consumption of sweets may be excessive now but she should not try and diet at her young age. It is very possible that as she grows over the next five years, her weight will be more in proportion to her height.

You don't mention your parents in this. Are they concerned? What are they doing about it? You could do more good by having a quiet word with them and see what they think. Perhaps as a family you could take more exercise together, doing fun activities, and jointly cooking meals. You're not going to achieve anything by the bullying and nagging you are currently doing.