A scene from “Unfinished Business”

Alicent: You are nearly a man-grown. How is it that you can be so shortsighted? If Rhaenyra comes into power, your very life could be forfeit. Aemond's as well. She could move to cut off any challenge to her succession.

Aegon: Then I won't challenge...

Alicent: You are the challenge! You are the challenge, Aegon! Simply by living and breathing! You are the King's firstborn son. And what they know, what everyone in the realm knows in their blood and in their bones, is that one day, you will be our King.