In your overnight bag, pack a change of clothes for everyone, including extra underwear, a t-shirt and socks because accidents, spills and vomiting can happen to anyone. Despite not really taking off their shoes, one of my kids lost multiple socks on the plane and in the hotel. Luckily most airlines give passengers a little package including a toothbrush and toothpaste, ear plugs, an eye mask and socks so we had a few extra pairs. I also packed snacks for our second long-haul flight in the overnight bag.