Fergie celebrated her baby-boy-to-be with a small, second baby shower on Sunday, attended by her Black Eyed Peas pals and more.

Dressed in a skin-tight mini-dress and metallic-toe pumps, the singer posed next to Will.i.am and apl.de.ap at the event, posting the image on Facebook and writing, "#UncleLove."

The 38-year-old partied at at first shower, her "gay-be" shower, on July 28 in Beverly Hills, thrown by her gay BFFs.

Fergie and hubby Josh Duhamel are expecting the little tyke to make an appearance in just a few weeks ...