13 Born of Empire by Sally Ann Melia

The last descendent of the ancient kings of England, Teodor never wanted to be King of Earth until he found he had a rival.
Embark on an epic sci-fi adventure with Guy and Teodor in ’13. Born of Empire – The Last Heir and the Unregistered Orphan’. Join two teens as they fight impossible odds, discover true friendship, and save humanity’s future.