 Complete the following phrase:  Born in Constantinople, John Kantakouzenos was the son of Michael Kantakouzenos, governor of the Morea; Donald Nicol speculates that he may have been born after his fathers death and raised as an only child. Through his mother Theodora Palaiologina Angelina, he was related to the then-reigning house of Palaiologos. He was also related to the imperial dynasty through his wife Irene Asanina, a second cousin of Emperor Andronikos III Palaiologos. Kantakouzenos became a close friend to Andronikos III and was one of his principal supporters in Andronikoss 