Laenor, the son of Corlys and Rhaenys Velaryon (and a second cousin of Rhaenyra), becomes the princess's first husband as a strategic move to unite the two most powerful houses and end the question of Rhaenyra's marriage. In the book, Laenor is not a bad man but one completely disinterested in marriage — or women at all. His best friend and "favourite" is killed at the wedding tourney, and rumours spread that he spends his time grieving his favourite rather than consummating his marriage.
Rhaenyra and Laenor's marriage produces three sons: Jacaerys, Lucerys, and Joffrey. Because none of the sons resemble Laenor — and because of Laenor's rumoured sexuality — rumours abound that the children are actually the sons of Ser Harwin Strong, a knight who becomes Rhaenyra's sworn shield.
In the book, Laenor dies relatively young, following a fight with one of his rumoured lovers. All three of his and Rhaenyra's sons die during the Dance of the Dragons, although two illegitimate children later appear and claim that Laenor was their father.