Hello, I am glad the little guys have been taken in by you. Did you quarantine them before adding them to your other budgies?
Just be wary they do in fact all get along and don't have any issues. DO they get out of cage tome to fly at all as having four budgies in a cage together they will need to be able get away from each other occasionally. Please read through the information in the Popular Forums section on the left of the page.