I need HELP BAD!!!!its my bird);?

well my parents had put a parakeet nest in my atiels cage i have 2 and hate if something happen to them their like my own kids well yeah my parents had tied the nest with an old blue ribbon and my 2 atiels would bite on it and 1 day 1 of them (toby) got 1 of his back toe tangle and my dad saw it and said his foot was dead and like his toenail was like an old broom but he's all cure now but later on my other 1 tweety 1 of her back toe got all brown it was dead then a few days later i notice that,that toe was gone and now i notice her whole foot was like how toby toe nail was like and im very worry about it too i been having her since 10.22.09 which like a year now what will happen to her or what should i do just looking at them make me feel bad and start crying and she'll just come closer to me looking at me crying like she know whats happening that im sad for what happening to her