shaking bird

I'm being told that my chick is shivering, but the gauge says it's at a good temperature, the chick is not wet/moist, and it's in a small closet so there shouldn't be a draft... What's this shaky movement about?

Hi everyone! I am new here, however I've been browsing for some time now. My mom adopted a love bird 13 years ago, he was already one years old. She was able to care for him -fine- for 10 years but the past 4 she is too busy. Once realizing his cage hadnt been cleaned in one whole year I...