Sparrow's Name Richie Gets the Shaft

10/16/2009 1:10 AM PDT BY TMZ STAFF
We just got hold of the birth certificate for Nicole Richie's 5-week-old son, but one word was suspiciously missing: Richie.

The newborn boy's full name is listed as Sparrow James Midnight Madden -- no big deal, until you remember Joel Madden and Nicole aren't married ... and their daughter Harlow's last name is Richie Madden.

What's another six letters on an already-mouthful-of-a-name?