Big Brother (Five Nights at Freddy's)

"Hey guys, I think the little man said he wants to give Fredbear a big kiss! On THREE! One....two...."

- Foxy Mask forcing his brother's head into Fredbear

Foxy Mask, or the Big Brother, is a major antagonist in Five Nights at Freddy's 4. He is the protagonist's abusive older brother, and is the one who caused the Bite of '87.

Five Nights at Freddy's 4
Foxy Mask is only seen in the minigames, particularly on Nights 2, 3, 4, and 5. His role as the child's brother, and not his father, is revealed on Night 5.

He hates his little brother, likely due to him still being a child, and has apparently abused the child to the point of him crying all the time. Five days from the party, he locks his brother in his room, laughing sadistically from the outside. Fredbear seems unfazed by what Foxy Mask is doing, only asking what he has done "this time." Fredbear constantly tries to help the child avoid Foxy Mask, guiding him with his words.

4 days from the party, the door is unlocked, but when the child enters the TV room, he jumps out from behind the TV with a Foxy Mask on, making the child fall on the floor and sob.

2 days from the party, when the child enters his bedroom, he jumps out from under the bed, causing the child to fall to the floor and cry again.

1 day from the party, Foxy Mask and his friends lock the child in the Parts/Services room, the child banging at the door sobbing.

On the day of the party, the child's birthday, Foxy Mask and his bullies, wearing the masks of Freddy, Bonnie, and Chica, surround the child tormenting him, the one in the Chica mask commenting that the child is pathetic. Foxy Mask suddenly gets the idea to force the child to be right next to the Fredbear animatronic, the child screaming and shouting as he is dragged over to him. Foxy Mask decides to force his brother's head into the animatronic, saying that it's a big kiss to Fredbear. He underestimates the strength of the mechanical jaw, only laughing with his bullies as his brother's head is stuck. The child's forehead gets stuck between the second row of teeth, and the machine overpowers his skull, crushing through and ripping out his frontal lobe, causing Foxy Mask and the bullies to stop laughing and look in horror.

Trivia

 * Due to him no longer laughing upon seeing what happened, it is likely he feels remorse for what happened or horrified by the event.
 * Some people believed he was the child's father, before Night 5, where he is revealed to be the brother.
 * He is rarely thought to be one of the night guards, Jeremy Fitzgerald, Fritz Smith, Mike Schmidt, or the anonymous one.
 * He can possibly be seen as the Bigger Bad, with Fredbear being the main antagonist.
 * He may be the child haunting Foxy, because some speculate that he was killed and was stuffed into Foxy by The Puppet.
 * Upon closer examination, the first three lines spoken in the Night 6 minigame, where the child passes on, are highlighted in grey text, revealing it is the brother at the child's bedside apologizing. The rest of what is said in the minigame, presumably belonging to the spirit within the Fredbear plushie, may or may not be the brother, with lines such as, "I will fix you." seeming rather strange for him to say,it might not be him and is fredbear who said this.
 * Some suggest The Killer, being a witness to the Bite of '87, was angered by what had occurred, and murdered all four of the bullies, turning them into Freddy, Bonnie, Chica, and Foxy. Foxy specifically being the Brother. This would be a more dramatic turn of events if the rumor of the Killer being the child's father is true, as he would essentially be murdering his elder son. It would also cast The Killer's motive into a new light, portraying him as a Well-Intentioned Extremist.
 * Some people believe that the brother is Phone Guy,the fact that he was a child in '87 and phone guy was WORKING at freddy fazbears pizzeria in 1987 may disproves this.