Flying - hand luggage essentials?

[Cwtches123]

Going on holiday at the weekend, family of 4, one child with autism and severe learning difficulties. Our main suitcases will be in the hold, our flight is around 3 hours.
What are your hand luggage essentials?
Just trying to make sure I haven't missed anything!!!

Tablet & charger
Snacks
Headphones
Empty water bottle
Travel sickness pills
Real book
Playing cards

The above pluss
Nose spray, helps against more severe pressure pains during take-off and landing
Hand towel/small towel
Hand sanitizer or wipes
Soft fleece blanket for kids
One change of clothes

Any medicine which has been prescribed just in case things go wrong with checked in cases or thing get delayed copies of prescriptions.
Favourite cup/ plate for autistic child as nothing else will do plus comforter

Spare pair of knickers for everyone.

If your cases get lost/delayed you can keep going in the same clothes, but you at least want clean knickers! If you're going to a warm place, you can put swimsuits in instead of underwear, they will do the same job, plus you can go swimming while you wait for the cases to turn up.

Medication, spare clothes if continence is an issue, snacks (anything likely to keep your dc happy), empty water bottle, noise cancelling headphones and tablet/phone preloaded with whatever interests them. Chargers and power pack (in case of no socket). Copy of diagnosis/dla award letter plus copy of any prescriptions (handy especially for theme parks ) Dd always took her special pillow toy and books but she's an obsessive reader (asd comes in many forms). If dc has enough understanding let them choose as much as possible, part of the behaviour problems we found came from frustration when she felt she wasn't in control.

Some good ideas, thanks. Most of that is already covered, not sure about a towel or blanket thought!

Small-towel or even a couple of face towels=Very useful if there is a accident, don't always need it but have in the past when dc spills something on himself or me. The blanket is for when my dc is exhausted, the one I have folds up very small, so he can be covered up for naps or if feeling cold. We take something like this with us flubit.com/shop/p/transformers-3-optimus-prime-cuddle-sleeves-fleece-snug-snuggle-blanket/FL5LVYLQ

Complete change of clothes as well as the knickers.

I can see the blanket could be useful for young children but it would be of no use to us!