Luke 2:44

But they, supposing him to have been in the company, went a day's journey; and they sought him among their kinsfolk and acquaintance.

but supposing him to be in the company, they went a day's journey, and they looked for him among their relatives and acquaintances.

but supposing him to be in the company, they went a day's journey; and they sought for him among their kinsfolk and acquaintance:

and, having supposed him to be in the company, they went a day's journey, and were seeking him among the kindred and among the acquaintances,

Assuming He was in their company, they traveled on for a day before they began to look for Him among their relatives and friends.