Her (tiny!) baby bump has arrived! Gwen Stefani rocked her very small baby bump for the first time Saturday, Sept. 28, after previously trying to conceal it in baggy clothes. The No Doubt singer showed off her growing belly while attending a friend's baby shower with son Zuma, 5, in Yorba Linda, Calif.

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Stefani, 43, wore a tight gray tank dress (exposing a black bra) for the outing, with matching black leggings. She also sported black high heels, shades and her trademark red lipstick. The "Hey Baby" singer looked absolutely glowing as she also wore her blonde locks down.

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A source revealed to Us Weekly earlier this month that the L.A.M.B. designer and her Bush frontman husband Gavin Rossdale were expecting their third child together. "It's very new and they just found out," the insider told Us at the time. "They're excited."

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The rocker has been keeping quiet about the baby news, but previously tried concealing her small baby bump just two days after the big reveal. On Sept. 5, Stefani covered up her pregnancy curves in super-baggy khaki pants and a draped, off-the shoulder top. She also wore a loose-fitted black tank top while out and about with Zuma on Sept. 11.

The third addition to the growing family will soon join Zuma, alongside the couple's eldest child Kingston, 7.

This article originally appeared on Usmagazine.com: Gwen Stefani Debuts Her Tiny Baby Bump in Gray Tank Dress: Picture