Wow, those parents are complete morons. Can you really name your child whatever you want there? If you try something like that in EU not only you will not be allowed to do it, but you would also risk your kids be taken away from you.
No, you're not taxed if you live in Spain, because this prize is given by "Loterías y Apuestas del Estado", but if you win a prize that doesn't come from them (like ONCE lottery and the likes), then you are.
You know, to make that milkshake you should have put those raisins in hot water for half an hour, so they can rehydrate and become soft, then they will blend.
This donation raised a lot of questioning in Spain, since they took that money from the budget dedicated to NGOs and international assistance.