The pharaohs had to have been born from the same womb, figuratively at least -- so, there were arranged, consanguinous marriages, and dynasties coming to sudden ends for some odd reason. :^)
Hatshepsut, for example, was married to her own father, then her brother (or maybe half-brother), and finally her nephew, in succession. During her regency she wound up ruling in her own right for some period of years, while taking up with her companion Senenmut (there's actually an ancient contemporary graffito showing the two of them naked and doin' it, I think she's even shown wearing the crown), and bearing her daughter Neferure. Hatshepsut died, apparently, of a tooth abcess, and her successor was her nephew (obviously in some form or other they had a common female ancestor back along the line, or he had a female ancestor in common with her father and his own grandfather).
I believe the nephew was then married to Neferure, but she didn't survive long. Neferure's tomb was found by Howard Carter, but has AFAIK never been "cleared" or examined by Egyptologists (the interior was visited, so it can be seen in some form in one of those quickie crappy Zahi-approved documentaries). Despite its isolation and obscurity, the tomb was apparently looted and wrecked, as most were, in antiquity.
Akhenaten, whose name was wiped from every inscription after he died, was afterward referred to as "the criminal of Akhetaten" (his shortlived new capital) and appears to have been unable to keep it in his linen robes -- there's scene that survives that shows him making out with his own underage daughter while Nefertiti watches, and a second child looks at the mother and points at the action. It's also likely that he fathered at least one child by his own mother.
The 18th dynasty ended in a big mess, with Tut making nice with the Amun priesthood, but portrayed at least once trying to walk with a crutch. After Tut died young, his successor Ay (his uncle) is shown performing the rites of burial in person, very unusual -- and Tut was buried in a big fat hurry. It can't be proved to be connected, but Ay's sarcophagus was found smashed to pieces -- probably just a tomb robbery, but clearly there was a succession crisis, actually three or four in a row, right at the end of the 18th.
Hatshepsut was the only child of Thuthmos I and his queen. She was never married to her father. She married Thuthmos II. He was her half-brother, Thuthmos I’s son by a harem girl. She and Thuthmos II had a one child, a daughter, Neferure. Thothmos II had a son by a harem girl, he would become Thuthmos III. Hatshepsut’s step-son (not nephew) was 5 years old when his father died. Hatshepsut ruled as Queen Regent of Eqypt for nine years since the boy was to young. In the last year as Queen Regent, she declared herself co-Pharaoh with Tuthmose III. As such, she continued to rule Eqypt for another 21 years. When she died, Thuthmos III assumed sole rule in Eqypt. He would rule as Pharaoh for another 34 years. He never married Neferure.
As Queen Regent and co Pharaoh, Hatshepsut’s statues and pictures show her wearing both crowns of Upper and Lower Egypt. What she is not shown wearing is a beard. Nor, in her royal titles, does she use the male forms of verbiage in her royal titles.
This information is from Joyce Tyldesley’s book “Hatchepsut”
You have the most wonderful way of bringing ancient stories to life! I learned NOTHING about Egyptian graffiti and your summary was brilliant. There’s a reason people enjoy writing Egyptian mysteries. The old civilizations were rife with scheming and intrigue. What fun!