Watch Carrie Underwood's Baby Start Crying When Daddy Sings, and Then Stop When Mommy Sings

CARRIE UNDERWOOD posted an awesome home video of her five-month-old son Jacob making it very clear which parent he wants to hear sing him a lullaby.  I'll give you a hint that you don't need.  It's not his daddy, Mike Fisher. 

Carrie's filming and it starts with Jacob on a mattress in a pretty good mood . . . until Mike starts singing, and the kid cries immediately.  But then Carrie starts singing and he stops.

Mike does it a second time, and the tears flow again . . . until Carrie starts singing, and the tears stop.  Mike tries it a third time, same result.

The video was posted yesterday on Carrie's Instagram page. 

Scroll down for some great celebrity comments.  Justin Timberlake wrote, "This is the greatest thing I've seen all year."  Kimberly Williams-Paisley said, "Oh my gosh, I'm dying."   Zach Swon wrote, "This is the best video ever."