It's name fit for the son of a lord.

Kourtney Kardashian on Sunday revealed her newborn son's name: Reign Aston Disick.

Kardashian posted a photo on Instagram of a tiny baby hand with the caption "Madly in love with my little Reign Aston Disick."

Reign, who was born Dec. 14 (Kardashian's older son's Mason's birthday), is the third child of Kardashian and her partner of nine years, Scott Discik. He joins Mason, 5, and Penelope, 2.

Kardashian and Disick's relationship has been the subject of much media scrutiny, especially as his roller coaster rides with sobriety are playing out on the latest season of "Kourtney and Khloe take the Hamptons," which is airing right now on E!