Egyptologists suspect that some time prior to Ramesses II's accession to the Egyptian throne, Muwattalli had reached an informal peace treaty or understanding with Seti I over Kadesh to avoid a clash between the two powers over control of Syria. In it, Seti effectively ceded Kadesh to the Hittite king in order to focus on domestic issues in Egypt.
Muwatalli had a wife named Tanu-Ḫepa and at least two children. One was Urhi-Teshup, who became king as Mursili III until his uncle Hattusili III deposed him. Another was Kurunta who became the vassal ruler of Tarhuntassa during the reign of Hattusili III. Another person named Ulmi-Teshup is suggested to be a third son of Muwatalli II but it is quite likely that Ulmi-Teshup and Kurunta are the same person.
^King (lugal) of Tarhuntassa (Bryce 1997, p. 296); apparently later Great King of Hatti (Bryce 1997, p. 354).
^Nerikkaili married a daughter of Bentesina, king of Amurru (Bryce 1997, p. 294).
^Two daughters of Hattusili III were married to the pharaoh Ramesses II; one was given the Egyptian name Ma(hor)nefrure. Another, Gassuwaliya, married into the royal house of Amurru. Kilushepa was married to a king of Isuwa. A daughter married into the royal family of Babylon. A sister of Tudhaliya IV married Sausgamuwa, king of Amurru after his father Bentesina. From Bryce (1997), pp. 294 and 312.