Kennedy Tennyson (born, simply, Ken) is the Galvanic Mechamorph son of Ben Tennyson when asexual reproduction was forced by a ray fired by Sii. Despite the form of reproduction, Julie Yamamoto is considered to be his mother and Ship his cousin. He was permanently fused with Julie from his birth during No Strings Attached, until her death in Ben 10: Alien Universe Unleashed.
- Merged with Julie, he was born and first appeared in No Strings Attached.
- He was detached from Julie in Ben 10: Alien Universe Unleashed, when Julie died. He then spoke and used the transformation of a hoverboard.