Blood Brothers is a mission in the game Grand Theft Auto IV, given by the character, Frank McCreary. The objective of the mission is to kill Frank's brother, Derrick.

1. Character: Frank McReary
2. Reward: Will be able to call Frank for a one-time offer to get rid of a wanted level later in the game
3. Unlocks: Clarence as a random character as long you spared him in the Holland Nights mission.
4. Achievements: NoneWikiCheats: Grand Theft Auto IV Walkthrough

1. Once your reach the location, use the stacked boards to climb up to the window scaffolding.
2. Use your sniper rifle to shoot your target.
3. You have a choice of killing either Frank or Derrick. However, there's not much difference in the outcome, except for the bonus of having the option of Frank removing your wanted level later in the game.WikiCheats: Grand Theft Auto IV Walkthrough

Francis (Frank) McReary is a croooked cop who has dirt on Niko Bellic's past. He threatens to expose this information unless Niko agrees to do some work for him. Though he's part of the larger McReary family, who play a big role in the game, Frank is not well-liked by his siblings because of his being a cop. For this reason, he acts fairly independently from the rest of the family.GTA4.net: Characters

• Frank McCreary is upset that Derrick is back in town. Apparently Derrick is threatening to talk to a journalist about the family.

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  Frank has plans to meet Derrick in the park off Bismarck in Lancet, and wants you to kill Derrick, to put him out of his misery.

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  When you arrive at the location, head over to the front of the building and jump up on the stack of boards. Take the window cleaning lift on top of the scaffolding to the roof. Use the lift to get to the top of the roof.

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  From here, this will be an easy, one-shot mission. Pull out your sniper rifle and shoot either Frank or Derrick. They are sitting side-by-side in the park on a bench.