Dodson mentions in his book about the royal families that Merneptah may have married Isetnofret III - the daughter of Khaemwaset - and not his sister.
For as far as I can tell they don't really know the parentage of Merneptah's wives.
Merneptah may have also married a Bintanath, but that could also have been a sister or a niece of his (as mentioned above). Seems they tried to keep it in the family though
I wonder if the royal princes could have married half-sisters who were offspring of lower ranked wives of Ramses? The princes would have had close to 50 sisters and half sisters to choose from.
I always thought it funny that Prince #23. Simentu married Iryet, the daughter of Benanath, A Syrian ship’s captain. So at least one dated outside the royal palace
I for the life of me can't remember if I mentioned it on this board, but there's a statue mentioned on the Griffith Institute website:
Kaemweset, Fan-bearer of the Lord of the Two Lands, and wife Renpeten(t)opet, Royal sistrum-player of (the statue of) Usermaetre-setepenre (Ramesses II) Montu in the Two Lands
Now Khaemwaset may have been a common enough name but I always wondered if this could be our famous prince.
The title of the wife is rather interesting as well: Royal sistrum player.