Rhaenyra and Daemon's sons Aegon, Viserys, and Visenya
In Fire & Blood, the book House of the Dragon is based on, Daemon and Rhaenyra go on to have two boys: Aegon and Viserys. Yup, another Aegon and another Viserys. They also have a daughter, Visenya, but she is sadly a stillborn baby.
The sixth episode of HBO's House of the Dragon raises suspicions about the bloodline of Princess Rhaenyra's three sons—Jacaerys, Lucerys, and Joffrey.
Aegon III, aka Aegon the Younger: Rhaenyra and Daemon's first child together. Aegon Targaryen, aka Jon Snow: Yes, he comes much later, when a song of ice and fire plays out. But he could be the prince that was promised, though that's still up for debate.
Rhaenyra was fond of Laenor's sister, Lady Laena Velaryon, who had wed Prince Daemon Targaryen after the death of his first wife, Lady Rhea Royce. Laenor and Rhaenyra had three sons together: Princes Jacaerys 'Jace', Lucerys 'Luke', and Joffrey 'Joff' Velaryon.
But how many kids does Rhaenyra have? Across the course of the first season, Rhaenyra gave birth to six children. All of her children were boys except the last pregnancy -- which ended in heart-rending tragedy.
Although Rhaenyra's mother's death initially made her fear the notion of bearing heirs, adult Rhaenyra Targaryen now has five sons in House of the Dragon – three healthy boys with Laenor Velaryon (fathered by Harwin Strong) and two silver-haired boys with her husband Daemon Targaryen.
In the books, they have three: daughter Visenya, who does not survive infancy; and two sons, Aegon III and Viserys II, who will grow up to be next Kings of the Andals, the Rhoynar, and the First Men.
Regardless of this, Rhaenyra's pregnancy was soon announced, and in the waning days of 114 AC she gave birth to their first child. Laenor wished to name the child Joffrey, but was overruled by his father, who named the boy Jacaerys. Rhaenyra gave birth to a second son a year later, who was named Lucerys.
Fatally attacked, Arrax fell into the sea, with Luce meeting the same fate. Their bodies were only found three days later, serving as a feast for crabs and seabirds. It is the news of her son's death that determines the desire for revenge and extermination of the Hightowers for Rhaenyra.
Rhaenyra's sons are bastards. They're the illegitimate children of Rhaenyra and Ser Harwin Strong (Ryan Corr). The issue of the children's legitimacy is an open secret at court, with people turning a blind eye because the king does.
Rhaenyra and Daemon now have two children—sons Aegon and Viserys—with a third on the way. Aegon the Elder is now married to Helaena, and it's mentioned that they have children. It isn't clear exactly which kids they've had yet, but in the books they have three: Jaehaerys, Jaehaera, and Maelor.
Lady Laena (Nanna Blondell) struggled for days with her labor, and with no hope for her or her baby, she made her way to her dragon Vhagar and commanded him to burn her alive. Though Rhaenyra has had five successful labors, she now suffers greatly and does so alone throughout her sixth.
So in addition to Rhaenyra's three sons with her first baby daddy Harwin (RIP), she has one daughter and two sons by baby daddy two, Daemon. Visenya, the daughter, is Daemon and Rhaenyra's firstborn child together. Sadly, Visenya does not survive her infancy.
In George R.R. Martin's fictitious history of the Targaryen family, we learn that Rhaenyra does eventually have children with her uncle Daemon: two boys named Viserys II and Aegon III, both of whom eventually become king.
Visenya Targaryen
According to the fool Mushroom, Visenya came out malformed with defects that resembled dragons more than men (although this is an unconfirmed account.) Princess Rhaenyra and Prince Daemon's only daughter was stillborn.
In 196 AC, the year of their marriage, she painstakingly produced a set of twins, Aegon and Aella. Another set, Visenya and Valarr, came in 197 AC. After her troubled deliveries, it was said Rhaenyra had nearly beaten a serving girl to death for having claimed the princess would die in labour.
Jacaerys, Lucerys, & Joffrey Velaryon: Rhaenyra and Laenor's three sons (like to actually be the sons of Ser Harwin Strong) are all killed during the Dance of the Dragons.
It isn't explicitly stated in the show, but because we learn after episode six that all three boys have dark brown hair — and despite Rhaenyra and Laenor's matching blond color — it has been strongly implied that they are actually the children of Ser Harwin Strong, the Lord Commander of the City Watch.
“When the babe at last came forth, she proved indeed a monster: a stillborn girl, twisted and malformed, with a hole in her chest where her heart should have been and a stubby, scaled tail. The dead girl had been named Visenya. “
One of the first times we see Rhaenyra as truly angry throughout the entirety of Season 1 is during the traumatic miscarriage of her daughter Visenya.
So, let's agree that he is (give or take) 16 years older than Rhaenyra. This places him in his early 30s when we first see him meet his niece. Yes, his niece. His teenage niece who we immediately realise he has a bit of a thing for.
Rhaenyra's sixth child, Visenya, is born with unusual birth defects that could have broad (and weird) implications.
In the book, Visenya was described as being born with dragon-like defects, including scales, a tail, and a twisted body. Rhaenyra's baby did end up having scale-like defects and a malformed body in House of the Dragon, which aligns with the occasional reports of Targaryen women bearing dragon-like stillborn children.
Rhaenyra's baby died during childbirth.
We only briefly see Visenya in the TV series, but Fire and Blood, the book House of the Dragon is based on, gives a detailed description of the malformed baby. According to the book Visenya, like Maegor the cruel's children, was born with scaled dragon-like skin and a small tail.