Albus feels like he has betrayed his family name by being sorted into Slytherin. Or does Albus actually want to betray the family name, like many fifteen-year-olds before him?

Harry grapples with guilt about people dying because of him. Albus grapples with the guilt of betraying his father. So he wants to fix that by undoing what makes his dad guilty, and by doing so he betrays basically everything. It's a vicious cycle.

This is a brutal exchange, and their relationship as father/son will be forever damaged. But neither one is lying. Is it possible to betray someone with the truth?

Harry continues to betray his son's trust by forbidding him from seeing his only friend. Will Albus ever be able to trust his father again?

It's the alternate-timeline Harry who bans Scorpius from Albus's life. This is the timeline where Ron and Hermione didn't marry. Is Harry different in this timeline, or is he the same as usual?

Scorpius and Albus think they're saving the day by keeping Cedric alive, but Cedric betrays them by turning to the Dark side.

Betrayal isn't always considered a bad thing in the Harry Potter universe. Snape is held up as a hero for betraying Voldemort and turning to the good side.

Harry's dreams are a mess. It's like he can't figure out if his own son might turn against him and betray him, or if Harry will betray his own son. (We think it's both.)

Delphi betrays Albus' trust by turning against him and using him as a pawn to revive her dead father Voldemort. With her, betrayal leads to more betrayal, as she wants Albus to ruin Cedric's reputation, again leading to the bizarro Harry's dead world.

Harry feels like he betrays many people simply by existing, and he carries a lot of guilt because of this.