Luke 2:43-45

and as they were returning [to Nazareth], after spending the required number of days [at the Feast], the boy Jesus remained behind in Jerusalem. Now His parents did not know this, but supposed Him to be in the caravan, and traveled a day’s journey; and [then] they began searching [anxiously] for Him among their relatives and acquaintances. When they did not find Him, they went back to Jerusalem looking for Him [everywhere].