A Budgie Lover

Guys, thanks a lot for your reply. Above chick is no more I took all of 4 chicks out of the nest because momy budgie began to stay outside the nest and chicks were crying loudly. That chick was youngest one. Often I returned them in breeding cage 1 by 1 to take food. All of them asked and got proper food from parents but the white one stopped asking food and started death starving. Anyway, now I am facing another problem! Another chick started starving while their parents totally stopped feeding. This chick is over 1 month old and always becoming mad to get food from its parents, sis, bro. None of them feeding it. Also he is always rejecting hand feed while its adult bro, sis accepting so nicely. Last time i see this chick is fighting to get food from its brother's mouth. It's getting sick too, what to do now? Any suggestion will be appreciated?

Expecting your suggestion. This budgie do not asking any food from its parents therefore they are not feeding this chick. Sickness symptoms: 1) Breathing too fast (can be observed from far), 2) Dark-brown droppings, 3) Max time closing its eyes, 3) It runs fast and seems can't see clearly, 4) Do not accept hand feed, 5) Almost no voice. There is its pics: