The 35 year old, who got engaged to 43 year old Orlando last year, announced the news during an Instagram Live video, where she told her 90.5 million followers: "I've always known I'm a mother, a mother to the kids."
At the end of the clip, which is thought to be a love ballad to her fiancé, the singer, Katy can be seen wearing a gorgeous white gown with a plunging neckline and turns to the side to reveal her gorgeous growing bump.
