Will a budgie foster two chicks?

My hens babies are nearly weaned. They grow so fast! I have here two more babies that need a mother. I put them in the nesting box and she (the hen) acts scared of them. I caught her pecking at them so I shooed her off... Is this stupid to think she might take care of them? She has not fed them at all today so I have been taking them out every four hours and feeding them and replacing them in the nesting box after. Her other babies love them they take turns flying in there and preening them. I even caught one of them regurgitating food for the youngest. Is this pointless? Does she just need time to adjust to them? Do I dare leave them in there all night? She wouldn't kill them would she? There are only two options for these babies I either hand feed or I find a foster mom.