Well if it's not causing issues between all the children in the sense that one says why can't I have what she's having .... And if it makes mom feel better then feed it... I wouldn't give a discount. All my parents send breakfast for their kids so everybody gets something different and I have never had a problem. so if they have never been away from mom I'm assuming they are around the 1 year mark and so they are not going to care if they have different things . I would just say to the parent " you aren't required to send food as I supply but if you prefer I feed yours then that's fine".