BA offers kids packs to children over the age of 2 as do VS (although with VS they are only available when flying from the UK)
QR when i last flew with them had soft toy aeroplanes that vibrated when you pulled the cord they also offered packs with baby essentials and were able to offer baby food for infants. They had toys for children also from what i could see but what i don't know
The terminal we were in at Doha airport had a big soft play area for children over 2
Swiss sometimes give out jigsaw puzzles to children