Olympic gymnast Shawn Johnson revealed the biggest mistake she's made as a mother — accidentally "waterboarding" her daughter.

OK, that sounds bad, but it really boils down to a misunderstanding regarding bottle tops work. According to the olympian in a YouTube video, when she had her baby, Drew Hazel East, she thought her daughter was lactose intolerant. Whenever she'd bottlefeed, the newborn would spit up the milk.

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“I was freaking out,” says the retired gymnast. So, she took the baby to the doctor and tried feeding Drew less. That's when she realized her mistake — the bottle size of the nipple on the bottle was meant for a six-month-old. To put into context what this was doing, Johnson says a friend laughed saying she was unintentionally "...waterboarding [her] child.”

While this was a learning moment for the new mom, the bottle sizes are pretty important. According to Child Safety Experts, it's important to choose the right bottle nipple size. Different sizes are meant for different babies, so it's recommended that parents keep an eye on how their baby is drinking. For example, a fast/medium flow hole might be needed if the baby is sucking too hard, but a slow flow is better if the baby is gulping. They also say it's important to ensure the bottle isn't propped up, as this position could cause the baby to choke.

Johnson — who won an Olympic Gold Medal in the 2008 Olympics — and her husband, NFL star Andrew East welcomed Drew to the world on Oct. 29, 2019. The Olympian revealed on Instagram that the whole process took 22-hours, and ended in a c-section. Still, Johnson admits she was a little stubborn during the event because she wanted a natural birth, so much so, she says she felt like a failure for not doing so.

Now, with a little more experience under her belt, she's not afraid to make mistakes and has no problem sharing what she learns along the way. Her fans are thankful for it too, as her posts are filled with parents who appreciate the honest look at parenting and the hiccups that come along the way.

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