Ethan Plath is celebrating his love.
"When high school sweethearts find each other there isn't much that can separate us," Ethan wrote on Instagram Sunday alongside a photo of the pair kissing in a gazebo. "Love you sweetheart."
Olivia replied on the post with a heart emoji and the comment: "I love you baby. You're right - been through a lot, and in the end it's brought us closer. I think I picked a winner."
Ethan's post comes a week after Olivia shared her own romantic Instagram dedicated to her marriage. "Just a little appreciation post for mon amour, who makes my heart smile," Olivia captioned a studio photo of the couple. "Tu es mon soleil."
Ethan responded, "You make my heart smile too. I love you Sweetheart."
It's no secret that Ethan's relationship with Olivia hasn't been entirely smooth sailing with the Plath family. Ethan's parents, Barry and Kim Plath, have been outspoken against Olivia — and it's all been seen on screen.
The TLC series shared a glimpse inside their feud during the season 4 finale in August. "I met Kim when I was 16 and she, when I first met her, made me feel important," Olivia said. "She kind of took me under her wing and in many ways kind of made me her new best friend. She was calling, emailing me every day."
"I trusted her more than I did my own mom, and at that point in my life, I really, really needed a mom figure. Because the mom I had was not nurturing, and also being one of 10 kids, it was really easy to feel overlooked and forgotten and I just really needed to feel important to someone."
Somewhere along the way, everything changed. "I think what changed is when I started to realize that I was just being used," Olivia continued. "I felt like I was only of value to her if I did what she wanted me to do."
Olivia recounted changing Ethan's computer password to cut Kim off from using his credit cards. "It went from like, 'I love you so much' to 'You have the devil in you,' and it just kind of changed overnight, she said.
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Ethan and Olivia married in 2018. They spent some time apart and questioned the status of their marriage in 2021, though they reconciled during season 3.