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Reported by Us Weekly

9021-Oh my!

Tori Spelling is going to be a mother for the fourth time this fall, when she and husband Dean McDermott welcome another baby.

And the actress and reality star, 38, kicked off summer 2012 a bit early in Malibu on Wednesday to show off her impressive pregnant bikini bod. Relaxing by the pool with daughter Stella, 3, Spelling showed off her bump in a sexy orange bikini.

PHOTOS: Meet her third child, baby Hattie!

The Oxygen star stayed hydrated with a cold drink and also kicked back with a nice read -- which just happened to be fellow mom Jenny McCarthy's Belly Laughs, all about the first year of motherhood.

PHOTOS: Pregnant bikini bodies

Baby number four joins Stella, older brother Liam, 5, and sister Hattie, who was born last October.

"All my friends keep asking me [if it was planned] and I'm like, 'Seriously? Hattie was one month old. Do you think it was planned?'" Spelling said at her CelabraTori book launch in NYC in April. "I was up all night with feedings."

PHOTOS: Tori's family album from her pre-90210 days to now

She joked that little Hattie "had a lot to say" about getting a younger sibling. "She was up in arms. She tossed that paci right out the door. Furious."