Constantine (son of Theophilos)

Constantine (Greek: Κωνσταντῖνος, romanized: Kōnstantīnos, 820s or 830s – before 836) was an infant prince of the Amorian dynasty who briefly ruled as co-emperor of the Byzantine Empire sometime in the 830s, alongside his father Theophilos. Most information about Constantine's short life and titular reign is unclear, although it is known that he was born sometime in the 820s or 830s and was installed as co-emperor soon after his birth.

Source: Wikipedia — Constantine (son of Theophilos) (CC BY-SA 4.0)