LOS ANGELES — Actress and reality TV star Tori Spelling announced Monday that she and husband Dean McDermott are expecting their third child.

“I know there’s been a lot of speculation, so I wanted everyone to hear from me,” she wrote on her Twitter account. “Its official…Dean & I are PREGNANT!!!!”

Spelling, 37, and McDermott, 44, have a four-year-old son, Liam, and a two-and-a-half-year-old daughter, Stella. McDermott also has a 12-year-old son from a previous marriage.

The couple appear together in the reality series “Tori & Dean: sTORIbook Weddings” on cable network Oxygen, and previously starred on “Tori & Dean: Inn Love” and “Tori & Dean: Home Sweet Hollywood,” also on Oxygen.