A fitness blogger fed up with online critics “mom-shaming” her over a bikini photo took them to task in a lengthy post.

Influencer Sia Cooper, who has over 1 million Instagram followers, slammed a commenter who scolded the mom of two for showing her backside.

Cooper, who is a nurse-turned-personal trainer, shared the woman’s critical comment along with a photo of herself in the very same bikini. (Sia Cooper)

“To show your gains you don’t have to show your behind like that,” the woman wrote, “you are a mother, think about what [sic] your children see your behind in your posts in the future, unfollowed.”

Cooper, who is a nurse-turned-personal trainer, shared the woman’s critical comment along with a photo of herself in the bikini.

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“The other day, I had posted a photo of myself in this very same bikini and was told to cover up... because I am a mother. Cue the mom-shaming,” Cooper captioned. “Since when were mothers no longer allowed to feel sexy? How do you think babies even got here in the first place?”

Instead of teaching her children to be ashamed of her body, Cooper said, she wants them to “see a mother who’s confident in her own skin.”

“There is no rule out there that states you can’t rock a bikini just because you pushed a baby out of your vagina at some point in your life,” she said. “In fact, that should make you worthy of one and so much more.”

Cooper shared that she grew up with a mother who “hated her body” and in turn made her hate her own body by “nitpicking” her size as a teenager.

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“I fought like hell to finally love myself and it wasn’t until a few years ago that I started wearing shorts again in public,” she said. “I would’ve given anything to have a body positive mama and I make sure that my kids see and feel this positivity everyday-not just with looks but with it all.”

Moms have enough to worry about, Cooper said, including postpartum and feeling “less than sexy” with all the demands of motherhood.

“It leaves us drained, depressed, exhausted, and staring into a mirror, looking at a former shell of ourselves that we barely recognize anymore,” she said.

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Cooper ended her body-positivity manifesto with a charge to moms everywhere to have permission to wear a bikini – regardless of what anyone else thinks.

“So mamas, put on your bikinis. You’ve earned it. Every woman deserves to feel comfortable in her own skin without society’s judgy opinions,” she wrote.

“Let the mom-judging stop. Motherhood is already tough as it is. We are damned if we do, damned if we don’t so stay true to yourself.”