Supermodel's super-brood!

Niki Taylor is pregnant with her fourth child, she announced on Twitter Wednesday.

Taylor, 36, posted two revealing TwitPics: In one, she holds an ultrasound snapshot over her (still tiny) belly with the caption, "Guess what's in this photo?"; in the second, she smooches husband Burney Lamar with daughter Ciel, 2, in her arms.

"YES!! We are expecting our fourth child!" the former Cover Girl spokesmodel wrote. "So happy and blessed!"

The beauty and race car star Lamar, 30 have been married for over five years. Taylor has identical twin sons Hunter and Jake, 16, with ex-husband Matt Martinez.