help about kids future

i and my husband are now absent of town and probably for a long time. it sas previously agreed that the kids should be with my parents and that is where there are since 4 months. they are with my parents because nobody from my hubby side shows concern on them and no one is really stable and the kids are not too used with them. the thing now is that they are with the parents in another town and he wanted them to leave my parents to come and continue school where they started with his mum (the mum is not all recovered because she had a surgery last two months) and the sister which is a person who does not know our to care of kids and we have four kids. I told him that changing nursery school or primary school to little kids has nothing to do with traumatism so far as they are with people they like and who like them. I need your advices to convince them to be realistic. the new school is just next to my parents house and cheaper than their former school. sorry for the length.