Refund
See my nephew got a something for a game without me and he spent all of my money ia there someway I can get it back
Purchases are considered final but you can try the 'report a problem' link to contact iTunes Support and see if they will refund or credit you : http://reportaproblem.apple.com
If the 'report a problem' link doesn't work then you can try contacting iTunes Support via this page (they will probably want the order number, which you can get from your purchase history) : http://www.apple.com/support/itunes/contact/ - click on Contact iTunes Store Support on the right-hand side of the page, then Purchases, Billing & Redemption
To try and stop it happening again you can use Settings > General > Restrictions on your device to turn off in-app purchases and to require your password to be entered for each download