- Photo: Sara De Boer/Retna Ltd.1 of 8
- Photo: Splash News2 of 8
- Photo: London Entertainment/Splash News3 of 8
- Photo: Fame Pictures4 of 8
- Photo: Cleyton Vitalino/Splash News5 of 8
- Photo: X176 of 8
- Photo: Jeff Vespa/WireImage.com7 of 8
By Kat Giantis
That rumor comes courtesy of Radar Online, which claims the couple, who are also parents to button-cute 21-month-old daughter Harlow, got a marriage license last week and said "I do" in a "top secret ceremony" on Wednesday.
Nicole's rep didn't respond to our request for comment on the knot-tying rumblings, but an insider tells Radar that the former party girl-turned-hands-on mom has been "talking more seriously" about making things legal since the August death of her onetime fiancé, Adam "DJ AM" Goldstein.
Adding to the speculation: TMZ reports Sparrow's birth certificate only contains the name "Madden," not "Richie Madden," like Harlow's.
This time last year, Richie hinted to People magazine that an aisle-walk would eventually take place, and it wouldn't be "top secret."
"When we get married, everyone will know," she says. "It will happen when it happens."
Lawfully wedded or not, the pair, who began dating in 2006, already has the married-with-children routine down.
"[Joel] has lost his hearing. Been asking 4 help round the house for 3 hours," Nicole tweeted on Thursday. "Wait, just said baseball & he's back! ITS A MIRACLE!"
Read more Hot Gossip
Demi Lovato snuggles with Wilmer Valderrama on today's Celebs Gone Social.Watch Video »
Jessica Alba flaunts her bikini body and shares photos from her work trip to Thailand on today's Celebs Gone Social.Watch Video »
Eddie Is Red Hot
Here are 5 things you may not know about Eddie Redmayne.Watch Video »
Check out some of Rihanna's wackiest outfits she's been sporting lately.Watch Video »
Taylor's Cute Cat
Taylor Swift shares an adorable video of her new kitten taking a catnap on today's Celebs Gone Social.Watch Video »
Khloe Kardashian rings in her 30th birthday with her family -- and her new boyfriend! -- on today's Celebs Gone Social.Watch Video »