"I SAID YES! I get to marry the man of my dreams," Emily, 28, captioned a photo of her 27-year-old Swedish fiance kissing her on the forehead.
"This is a moment I've dreamed of since I was a little girl and it's more than I could have ever imagined because it's truly with my perfect person. I can't wait to grow old and laugh with you forever 12/11/2020."
One day later, Emily captioned a video of her marriage proposal, which someone attempted to secretly film behind a bush from a distance.
The video caught William down on one knee proposing to Emily during what appeared to be a hike. The blonde beauty was wearing pink sweatpants, a gray sweatshirt and black sneakers.
"You're really going to do this right now -- right here?!" Emily can be heard asking in the video.
Emily then sobs with her face in her hands before accepting the ring and telling William that she loved him.
"Proposal. How he did it. I never imagined that I would be getting proposed to in sweatpants, hair in a bun and a spray tan....but truly it could not have been more perfect," Emily captioned the video.
"William Karlsson, thank you for loving me for me. You love me when I'm at my worst and when I'm at my best. I don't know how I got so lucky. I can't wait to do life with you forever."
Following Ben's stint on The Bachelor, he and Lauren starred on a season of Ben & Lauren: Happily Ever After? on Freeform.
Since Emily and Haley often appeared on the series as Lauren's best friends, the twins took over for Ben and Lauren and starred on the subsequent season of thespinoff, which was renamed The Twins: Happily Ever After?.
Freeform only aired one season of The Twins: Happily Ever After? in 2017.