Buy your toiletries when you get there. Make sure you have the lightest possible bags to take with you. About 5 years ago I decided to weigh my cases. They were 6 kilos each with nothing in them. I bought lightweight trolly bags on eBay.
3 pairs of knickers max. You wash as you go in the sink
2 bras. One white and one black. As above.
Two swimmers. As above.
Sarong for during the day. Again can be washed through.
Buffet restaurants won't be dressy so don't worry about taking a lot for that. May be a couple of pairs of trousers and vest tops. A cardi as a cover up?
Shorts and a couple of t shirts for days out.
Kids stuff doesn't take much space if they are little. 14 t shirts and 7 shorts each should be enough. Crocs on the plane. They'd probably get all of theirs into one 15 kilos giving you a bit more. Kids can wear clean every night and wear that outfit the next day.
Kids need 2 swimmers. One on and one washed and drying.
DH would need shorts and t shirts, pants and may be long trousers for dinner? Couple of shirts.
You could even buy your toiletries in boots airside at the airport as you won't all need hand luggage. How much hand luggage are they giving? Only you can pack extras into hand luggage but mainly I do electricals, toys etc in cabin bags.
How old are the DC?