How to deal with family

Not sure if this is the right group to post in lol. We're hoping to get married in October next year, and we haven't got many people to invite so we will be choosing the silver package at our venue which is a really great price and only allows up to 25 guests, which I don't even know if we'll fill. My parents are divorced and both remarried, they dislike each other but it's not the worst. They can be civil. However, my FH's parents are much worse. They've been separated for a number of years (not officially divorced) but they really really don't get on. They can stay away from each other, but they makes things feel so awkward and just stressful. We will probably seat my mum with his mum and my side of the family and my dad with his dad. My FH is worrying so much about our wedding day saying he's dreading the socialisation between everyone because of the awkwardness and he doesn't want to feel like he's having to babysit everyone because he can't have everyone together and I know what he means. Anyone got any advice for this??