Ah, yes, in that case you would need kitty's services, for sure. Songsheet sourced five ferals for the job her way! Approachable enough, but they love their little miceys!
Yes, that'll be Dad on the go twice as hard now, Sheikh. Do you know what they are? You could help if you could determine what - most garden birds love mealworms, grubs, anything like that which you might be able to help him make up for the deficit in hunting assistance. Any pet store will have them, so if you could chuck those out early morning on the wall for him, he can stuff the babies fairly full before Felix is fully awake! If you can help him out (and I think he will feel you owe him that!), he may well single-parent the babes until they fledge and then self-feed to a degree. Best of luck.
PS: if you can't get the mealworms (although pet shops will stock them for reptile and spider lovers), then pro tem a little grated cheese, some dry porridge oats, thin pieces of ham cut into small bits, leftover egg, etc. would be most helpful and do them no harm. If you could add half an egg for them when you're scrambling some for brekkie and leave that out, it would be excellent protein for them.