Last week, Australian mom and blogger Siobhan Rennie posted a photo of herself feeding her 13-month-old daughter, Aoife, with a bottle.

It may seem like an unremarkable post, but in the midst of the countless “brelfies” that inundate the parenting social media sphere, Rennie’s bottle-feeding photo is somewhat of a rarity.

That’s why she’s using her powerful Instagram post to fight against the mom guilt that often accompanies mothers’ breastfeeding decisions.

”I still feel guilty every day that I’m not breastfeeding Aoife anymore,” Rennie wrote in the caption. “Because mum guilt is a HUGE BITCH.”

The mom, who also has a 2-year-old son, explained that she stopped breastfeeding her daughter for many reasons, including latching problems, scheduling challenges and mental health concerns.

“At four months we called it quits, and it was such a painful decision,” she wrote. “Life definitely got easier; we were all a lot happier. But I still, eight months on, think I gave up too easily. I didn’t, I know that, but I still can’t help being really hard on myself...”

On top of her inner emotional struggle, Rennie said strangers have added to her sense of guilt. Like a woman at the park, who had given her a judgmental stare for bottle-feeding her daughter earlier that day.

The mom responded to the incident with a powerful message for her fellow parents. “The thing is, FED is best,” she wrote. “Aoife was (and still is) more satisfied on the bottle. It doesn’t matter how we feed our babies, as long as it’s safe and they’re nourished and happy.”

She concluded, “Never doubt your choices, you have to do what’s right for you and your whole family ― whether that be breastfeeding until they’re toddlers or never being able to even start, And tell mum guilt to just F OFF”

Rennie told The Huffington Post, she always tries to promote the importance of moms supporting each other through her Instagram account and blog, MeOhMy.

”There’s too much judgement out there about the different choices a mom can make,” she said. “As long as it’s safe for the baby, why should we judge another mum for however she chooses to ‘mom’?”

Rennie added that she’s faced a lot of judgment over her nearly three years of motherhood. When she decided to increase her son’s daycare hours when her second child arrived, one mom told her online, “Why have another baby if you can’t even take care of the one you have already?”

“Daycare or not, breastfeeding or not, it’s all the same ― we make the right choices for us and our family, and it’s no one’s business but our own,” the mom said.

Rennie told HuffPost her wish is simple: to see moms stop judging other moms.

“I know it’s partly inherent, but if you have an opinion and it’s negative, just keep it to yourself,” she said. “You don’t need to criticize anyone publicly, or stare disapprovingly. We’re all doing the best we can, and no one is perfect.”