African green finch

Question
My Dad has had an African Green singing Finch for 5 yrs that has been healthy and singing. Dad had to move to a nursing home two weeks ago and could not take his pet with him.
My brother still lives at Dad's apt with the bird but the finch is now looking very ill.
In the past two weeks he has lost feathers (possibly pulling out most of his tail feathers) and is even turning grey. He is not singing.
Is this from grief?  What can we do to help him?

Answer
Finches are not accustomed to change and when the person who cares for them has changed, it can be stressful. It also could be because your brother cares for the little guy differently than your dad did. Here are a few things you can do:
Get tips from your dad on what he would do to care for the bird
Get a heat lamp on the cage (the kind found in the reptile section of pet stores) and have it around 28C
Get him a buddy-preferably a girl of his own species. Having a companion will help lessen the stress.