My sister is obessesed with her pet bird --- it was my bird at first, but she kinda just took over her, while?

There is no such thing as being obsessed or over doing it when it comes to keeping a bird clean, healthy and happy. Just be glad she is being so responsible and taking the best possible care of the bird. I wish all I had to do was buy the food for mine and someone else would do all the hard work. Count your blessings.