Furthermore: Theon married Sansa and became LP (for some reason because I helped Robb I became his vassal). Theon's son Eddard won independence after Robb's son (also Eddard) turned out to be a nutter. Later, he conquered the Westerlands, and made Sansa Queen of Harrenhal and his sister Queen in the North, inheriting both. And as we see, Eddard's son Dagon won the Iron Throne.

So Balon could have ensured his descendants sat the Iron Throne for generations to come...

... but instead he chose to add a few more shitstained rocks to his collection. Falling off of Pyke was truly the most intelligent thing Balon did.