Luke 2:43, 47-50

When they had finished the days, as they returned, the Boy Jesus lingered behind in Jerusalem. And Joseph and His mother did not know it

And all who heard Him were astonished at His understanding and answers. So when they saw Him, they were amazed; and His mother said to Him, “Son, why have You done this to us? Look, Your father and I have sought You anxiously.” And He said to them, “Why did you seek Me? Did you not know that I must be about My Father’s business?” But they did not understand the statement which He spoke to them.