I think I would use 10% for just splurging and invest the rest into the future of our family.
If a tournament win 1 million dollars what a dream that will meet? Go on trips,money to friends, relatives,donations or what? Specify in short which is your dream, you may fulfill in a good day.
I would give half of the money to people I know and really need.The other half I would try to multiply it while enjoying my new life.
if I win a Sunday million I would play so many tournaments and I would try to change my status VIP and become a supernova