Hi Evelyn,
If the chicks are all weaned then no, do not put them back with the parents. You didn’t mention what species these are? But regardless, once chicks are weaned, they need to be separated from the parents or the parents will get aggressive with them. This is just instinct, and in the wild it keeps related birds from breeding. You should never let related birds breed with each other, and they don’t know any better. When you breed birds, there are certain responsibilities you have. As soon as all chicks leave the nest box, you have to remove it, or the parents will try to nest again too soon. If they do, a lot of parents will stop feeding the chicks instead of weaning them, and the chicks starve to death. As I mentioned, once the chicks are weaned, remove them from the parent’s cage. But do not give the parents their nest box again for 6 months. Your pair needs to be rested for 6 months, without a nest box, in between every clutch whether the eggs hatch or not.
Thank you for asking Lafeber,
Brenda