Even Scripture isn't backing you up with this statement.
And it came to pass, that, after three days, they found him in the temple, sitting in the midst of the doctors, hearing them, and asking them questions. And all that heard him were astonished at his wisdom and his answers. And seeing him, they wondered. And his mother said to him: Son, why hast thou done so to us? behold thy father and I have sought thee sorrowing.
-Luke 2: 46-48
LOLOLOL!
Hey, you're a heretic! Buggman says so.
Those nasty Bible quotes can get in the way of truth sometimes.
You might try picking a passage which refers to a time a bit later than when He was twelve years old. As a child living under the Torah, He honored and obeyed His earthly parents. As the Resurrected Lord, they honor and obey Him and call Him Lord, just as David does.
More importantly, Mary provides a very clear message.
For 10 points -- who can say the last words Mary is quoted as saying in the Bible?
If you can't then you don't understand the importance Mary has for all Christians -- Catholic or not.