Stephanie Pratt bodyshamed her sister-in-law Heidi Montag on Instagram.

Heidi Montag and Spencer Pratt

Heidi Montag and Spencer Pratt

Stephanie left fans confused when she shared a picture of Heidi in a bikini on a beach and wrote "Yay Heidi’s pregnant! I hope she has a little girl this time. Cute bump."

She also posted a picture of her brother Spencer Pratt in shorts and wrote: "I wonder what my brother is having."

But Spencer, 37, quickly clarified that he and his wife are not expecting a sibling for their son Gunnar, three, and that Stephanie was just being spiteful.

One fan wrote to Heidi, 34: "Stephanie just posted ur pregnant but I don’t see that u posted it. Wtf I hope she’s not revealing it for u (sic)."

Spencer replied, saying: "Heidi is not pregnant. Just being body shamed."

Stephanie previously lashed out at Heidi and Spencer, calling them "toxic".

She said: "I'm not going to pretend that Spencer and Heidi are good people like I was doing for most of the series [of 'The Hills'] for my parents. For the s*** they've done to me recently, I'm done. They're the most toxic people I've ever met."

Spencer also said he no longer considers Stephanie family.

He explained: "She's a great aunt to my older sister's kids, but we've not been close for 15, almost 20 years. So long that she wouldn't be in [my son] Gunner's life."