I heard the Messenger of Allah (May peace be upon him) explaining the verse “As for the youth his parents were people of Faith,” he was created infidel the day when he was created.
Sunan Abi Dawud Book 42, Hadith 111
← Previous Hadith The boy whom al-Khidr had killed was created an infidel. Had he lived, he would have moved his parents to rebellion and unbelief.

Sunan Abi Dawud Book 42, Hadith 110 Next Hadith → Ubayy b. Ka’b told me that the Messenger of Allah (May peace be upon him) said : Al-khidr saw a youth playing with boys. He took him by his head and uprooted it. Moses then said : Hast thou slain an innocent person who had slain none.

Sunan Abi Dawud Book 42, Hadith 112