Around £200-£250. I never normally spend that much but he wants a bike (in particular a Spider-Man bike so I can't get a cheapo one to minimise the budget )
I'm terrible, I spend about £300 each (less on the youngest this year but will increase as he gets older to meet the older ones budgets) but apart from a few bits on their birthdays its the only time they get new things unless they have saved up themselves with their pocket money from FIL