He was named after both his paternal grandfather Jim McCartney and his father, whose full name is James Paul McCartney, as well as Linda's late mother, Linda Louise Eastman.
Pojmenován byl po svém dědečkovi Jimovi McCartneym a po svém otci, jehož celé jméno zní James Paul McCartney, ale také po Lindině matce Louise Eastman Linder.