Just going to throw out ideas regardless of cost, of course adjust to your budget.
Older boys' clothes apparently are in short supply, although not all refuges take boys over 12. If it does take boys over 12, male toiletries might be received well.
San pro, that must be really humiliating to ask for or try to improvise, it can be expensive too.
Nice toiletries? Kettle sounds good. Blankets? Thinking something comforting, safe, relaxing/distracting, something which feels like "mine". Colouring stuff for children - complete sets of pens/crayons rather than having to share. Perhaps a nice notebook/journal. Books as long as they aren't triggering or upsetting. Treaty foods. Portable CD/DVD player.
But then practical stuff is probably a priority too - baby equipment. Pushchairs, slings, sleeping bags, bottles, warmers, mobile/playmat etc for something nice. Weather proof clothing, especially for children - wellies, raincoats, warm coats, gloves, scarves, hats, fleeces, vests. Good quality shoes, some of that waterproofing spray for shoes. Nice fluffy/warm towels, hooded towels for babies. Children's toothpaste.
Something to keep children busy for longer periods - open ended toys, paper and pens, packs of cards for older ones, some of those books with rainy day activities or things to do on a car journey/plane (good for games you can do in a small space with few props). Story CDs for different ages or song CDs for little ones. Cheap earphones. Sport stuff if the refuge has a garden - a ball, a frisbee (perhaps more summery). Book on how to make paper aeroplanes or other things which don't require hundreds of things from a craft shop but just stuff which is extremely everyday. Guinness book of records (keeps you going for ages).
Top up cards for different phone networks, if they don't expire. Gift cards for grocery shops or Boots or Superdrug, then they can buy their own toiletries and medicines. Lemsip if you're allowed to put medication in.
Comics/magazines. Branded cereal, with a free toy.