Babysitting is a mission for Derrick McReary, Packie's brother in Grand Theft Auto IV. In this mission, Niko and Derrick help a North Korean named Kim Young-Guk smuggle a boat full of counterfeit 100 dollar bills into Liberty City on a boat. This mission introduces the Rocket Launcher, the most powerful explosive weapon in the game. Niko meets Derrick in a boat. He takes Derrick in the boat to Kim Young-Guk, a Korean criminal that is wanted by the police for counterfeiting money. Niko and Derrick follow Kim and use guns to blow up a few boats that want to use Kim's counterfeit money for themselves.