Luke 2:43

And when they had fulfilled the days, as they returned, the child Jesus tarried behind in Jerusalem; and Joseph and his mother knew not of it.

Luke 2:43 · King James Version

In other versions

and when they had fulfilled the days, as they were returning, the boy Jesus tarried behind in Jerusalem; and his parents knew it not;
ASV
And when the days of the feast came to an end and they were going back, the boy Jesus was still in Jerusalem, but they had no knowledge of it:
BBE
and had completed the days, as they returned, the boy Jesus remained behind in Jerusalem, and his parents knew not [of it];
DBY
and when they had fulfilled the days, as they were returning, the boy Jesus stayed behind in Jerusalem. Joseph and his mother didn't know it,
WEB
and having finished the days, in their returning the child Jesus remained behind in Jerusalem, and Joseph and his mother did not know,
YLT
And when they had fulfilled the days, as they returned, the child Jesus tarried behind in Jerusalem; and Joseph and his mother knew not of it.
ENG
And when they had fulfilled the days, as they returned, the child Jesus tarried behind in Jerusalem; and Joseph and his mother knew not of it.
WBT
When those days were over and they were returning home, the boy Jesus remained behind in Jerusalem, but His parents were unaware He had stayed.
BSB

⁴¹Now his parents went to Jerusalem every year at the feast of the passover.

⁴²And when he was twelve years old, they went up to Jerusalem after the custom of the feast.

⁴³And when they had fulfilled the days, as they returned, the child Jesus tarried behind in Jerusalem; and Joseph and his mother knew not of it.

⁴⁴But they, supposing him to have been in the company, went a day's journey; and they sought him among their kinsfolk and acquaintance.

⁴⁵And when they found him not, they turned back again to Jerusalem, seeking him.