On April 12, 2020, Kara Keough Bosworth and her husband Kyle experienced every parent's nightmare: losing a child. Their son McCoy suffered shoulder dystocia and a compressed umbilical cord during delivery and died when he was only six days old.

A year after her "darkest day," the former Real Housewives of Orange County star shared heart-wrenching side-by-side photos of her late son and newborn baby boy Vaughn, who was born on March 21, 2021.

"Last year on April 12th, we held McCoy for the last time. Remembering those moments will haunt me forever," she captioned the emotional post. "Feeling robbed and grateful today as I also remember the moment Vaughn landed on my chest. Not sure I've ever experienced happiness like that."

Keough Bosworth, who also has a 5-year-old daughter named Decker, kept this pregnancy private and didn't introduce Vaughn to the world until he was born. And while she carried him, she also carried the grief of losing his big brother. "That journey from our darkest day to the brightest hasn't been easy. But we kept going," she wrote. "When people would say, 'I can't imagine what you're going through,' I tried to ignore that I'm living the unimaginable, and instead I focused on the fact that I'm 'going' through it. It isn't stagnant. It's movement. We're headed in a direction. So we kept going. And when people would ask, 'How are you doing?' I'd reply, 'I'm doing.' Because sometimes, that's enough. In my case, that was everything."

"When I'd get frenzied in my grief, my doula @4thtrimesterfitnessmethod would remind me to just do the next thing. I'm so glad the 'next thing' was you, Vaughn Mack," Keough Bosworth continued. "You're not the next best thing; you're the best next thing. You're not a replacement; you're an extension. Thank you for making this April 12th so much better than the last, sweet boy."

Though she kept her pregnancy a secret, Keough Bosworth openly pays tribute to McCoy on the sixth day of every month. She's also shared messages to other mothers who've gone through the unthinkable.

"All these photos, of mamas dressed up with their arms full of their babies... and I just want so badly to be that mama, with my arms full of my babies," she wrote on Thanksgiving. "Instead, today is hard. Feeling thankful AND robbed is hard. To the others having a hard day today, you're not alone."

To the mamas who know the indescribable pain of losing a child, remember those important words: You're not alone.