We can't stop laughing! Kelly Osbourne's latest Instagram photo had fans doing a double take after they double tapped.

The former Fashion Police host shared a pic with her sister-in-law Lisa enjoying a relaxing pool day on Sunday.

"#SisterSunday #DivaLife with my sis @mrslisao #BestPoolDayEver," she captioned the pic of the pair in matching bikinis.

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However, it wasn't long before followers noticed something weird peeking out behind the duo.

"Am I the only one who sees a frickin' ghost in the left corner?" one fan commented before another added, "I never noticed your tiny left arm before! Lolllll."

Kelly, 32, quickly responded to the hilarious photo fail.

"Check out my sexy baby arm! The most hysterical yet #epic #PhotoFail! This is instant karma For trying to hide my fat ass behind Lisa while holding my niece," she jokingly explained on the social media platform.

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The always candid star recently opened up about her weight loss transformation in her new memoir, There Is No F–king Secret.

"I was a f–ked-up ugly duckling who somehow emerged a lavender swan," she wrote in an excerpt shared by Us Weekly. "I went from being the girl mums told their kids to stay away from to the girl mums follow on social media and stop in the street to ask for advice about their own daughters’ struggles."

kelly osbourne weight

She also revealed she secretly struggled with Lyme Disease in the past.

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"I had started entering my symptoms into online quizzes, and the results kept coming back Lyme disease," she added. "For the first time, someone listened to me, and I got tested. The results were positive: I had stage III neurological Lyme disease."

We think Kelly is looking fabulous — baby arm and all! To see how much the Osbourne family has changed, click through the gallery below!