Lisa Rinna, 55, rocks bikini, dismisses haters. Why do moms get so much pressure about what not to wear?

This is an opinion piece by Lindsay Powers, author of the forthcoming book, You Can’t F*ck Up Your Kids. Have you ever felt judged as a parent? Check out @NoShameParenting.

Reality star Lisa Rinna has a few choice words for anyone who dares judge her bikini body.

The 55-year-old mom of two recently posted a photo of herself in a tiny Fendi bikini on Instagram. Shortly after, a website compared her to 26-year-old Miss Universe Olivia Culpo, asking, “Who wore it better?”

Rinna’s response? “We both looking f*cking awesome. I’m 55, she’s in her 20s. The end.”

People were quick to praise the Real Housewives of Beverly Hills star. “The. End,” Kelly Ripa, who has also been called out for wearing a bikini at 47, wrote on the Instagram account CommentsByCelebs, which first posted Rinna’s clap back. Added another fan: “Dayum Lady! You are killing it. That bod after 2 kids and 50.”

I actually love wearing bikinis, even though my body has changed since I’ve had both my kids. I recently purchased a one-piece while on vacation and thought, ugh, finally a “mom” bathing suit. But I believe there’s nothing I should — or shouldn’t — wear, despite being 36 and 15 pounds heavier than I was in college. The only thing my kids will remember was if I wore a bathing suit and played, not what size or shape it was on my body.

Of course, this all begs the question: WHY do we feel the need to call out what women wear, especially when they’re over a certain age, and even more especially when they’re mothers?

Certified sex coach Gigi Engle says this attitude is no surprise. After you become a mom, “society doesn’t want to see you as a sexual being anymore,” she told me for my forthcoming book, You Can’t F*ck Up Your Kids. “They just want to see you as a mom and caretaker.” Ditto turning a certain age. Data has shown that women over 22 years old are considered less attractive by men.

And if you’re sexy in public? Forget it. “You’re neglecting your motherly duties, and you’re making your child view their mom as anything other than this ‘mommy character,’ which is so traumatizing,” adds Engle sarcastically.

From an evolutionary standpoint, we are wired to see younger women are more sexually attractive because they are more fertile, relationship expert Dr. Wendy Walsh tells Yahoo Lifestyle. Men have also created a “sexual double standard,” she adds, to shame women who have more sexual partners, or who appear more sexual. “This was designed to control whom women share their eggs with. Thus, if she’s worried about her ‘reputation’ she’ll be less likely to expose her eggs to many men. Perhaps the worst part of the double standard is that men made the rules but women enforce them to gain favor in men’s eyes.”

Designer Samantha Sleeper, whose eponymous bridal clothing line features gowns for breastfeeding mothers, calls the judgment “absurd.”

“No one is like, ‘Look at that 50-year-old man with his shirt off. No, he’s People’s Sexist Men Alive!’” laughs Sleeper, a mom of one. “The idea that anything is forbidden at a certain age is an antiquated concept of what it means to be a woman.”

Elizabeth Hurley, 53, sparks endless headlines every time she dons a two piece — which is quite often, given that she owns her own swimwear line.

“There has been such a big movement in the last few years, which I think is such a positive one. That not everybody has to be 24 [years old] and 90 pounds,” Hurley once told Yahoo Lifestyle. “People are feeling much more comfortable with their own body shape, with their own body type, and I think that’s a really great thing. At any age, it’s fantastic.”

Indeed, after Helen Mirren was photographed in a red bikini at age 62, women seemed to get the message that you don’t have to pack away your two-piece the second you hit 30 or become a mom. Mirren’s confident stance caused bathing suit sales by women over age 50 to soar, according to one survey. (The Oscar-winning actress has joked that the “bloody photograph of myself in a bikini” will “haunt me for the rest of my life.”)

Says Sleeper: “You shouldn’t stop feeling like you have a sexual identity after a certain age!” Mother or not, “a woman is multifaceted.”

Mom Alyssa Shelasky calls the pressure to look a certain way after giving birth “ridiculous.”

“Women and mothers should wear whatever they want!” Shelasky tells Yahoo Lifestyle. “For me, my style changed after becoming a mom — and it’s so much better now because it’s all around comfort. Comfort looks so sexy on women. I love wearing mom jeans and sneakers. And you better believe I’d rock a tiny bikini or go topless for that matter if I wanted to! Personally, I think I look better with clothes ON, but that’s my choice. If I wanted to wear a tiny bikini, I’d do it happily and not give a sh*t what anyone thought about it. In fact, I’d say: bring it.”

If you don’t want to “flaunt your bikini body” after having kids or for any other number of reasons, that’s obviously fine, too. You can wear whatever you want, whatever your age, whatever your body shape, no matter if you have kids or not.

And if anyone has anything to say about that? Forget them. “Usually when somebody is really judgmental or has these blanket statements about what people should or shouldn’t wear, or what a father or mother should or shouldn’t look like,” Sleeper says, “it really says more about them than you.”

Read more from Yahoo Lifestyle:

• Elizabeth Hurley, 52, breaks the internet with bikini dance

• Plus-size fashion blogger calls out Revolve’s influencer press trip: ‘Where is the diversity?’

• Khloe Kardashian thinks she’s getting a double chin

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