But Jacob's dad, Amy's ex-husband Matt, wasn't in the photos that Jacob and Isabel posted on social media showing the April 22 bash!
Isabel posted a picture on Instagram of herself, her own father, Jacob, and Amy with the caption, "One of my favorite parts about the day was how much these two, my dad and Jacob's mom got along ? Even though Jacob and I have been together for three years, they met for the first time this year…it was such a beautiful day."
To accompany another photo of her and Jacob kissing, Isabel gushed, "On Sunday, we had an engagement party and it was a wonderful day full of loved ones. We are so incredibly blessed to be walking into this season of life with so many amazing people by our side and endless support. My heart wanted to burst all weekend and I cried more than once. Thank you to those who came, celebrated, and shared your hearts with us on this special day. We love you all so much ???To my fiancé, I just can't wait to marry you. #rockandroloffwedding2019 #morephotostocome"
She also posted a picture of beautiful party flowers on the farm, but it appeared Matt might not have been there as he wasn't shown in the public pics Jacob and Isabel shared with fans.
Jacob didn't reference his dad, either, writing as an Instagram caption, "We had our engagement party. So good to have Izzy's side of the family and friends see the farm and meet all my people. To be honest, though, I was very much preoccupied trying to figure out how I got so lucky? She was seriously breathtaking in that skirt... I've loved this lady for four years but boy does she still impress me... in more ways than one."
Amy gushed online, "What an awesome day celebrating Jacob and Isabel's engagement with a party! Beautiful to bring two families and friends together. They're getting married next year. Thanks for everyone's encouragement and support. I'm blessed with really great kids."
Jacob, 21, who no longer appears on the Roloff family reality show, popped the question to Isabel on Christmas, Dec. 25, in Iceland.
But secretive Jacob didn't announce his engagement until a month later, Jan. 27, via Instagram.
As RadarOnline.com reported last weekend, Amy announced on her Instagram account that she was throwing a party for the two artsy travel enthusiasts who are head over heels in love.
Meanwhile, Amy and ex-husband Matt divorced a couple of years ago and both have significant others. Matt is enjoying his time with galpal Caryn Chandler, while Amy recently got home from a romantic cruise with beau Chris Marek.
As Radar readers know, this weekend, Amy is bonding with her only daughter, Molly, as she announced a "road trip" to see her and the camera-shy girl's husband Joel Silvius in Spokane, Washington.
But on April 22, it had been all about her free spirit son, Jacob.
Although Jacob mended fences with his parents and siblings two years ago after a brief estrangement, he recently unfollowed his brother Jeremy's Christian marriage blogger wife, Audrey.
As Radar previously reported, Jacob left the show in 2014 after later explaining he felt "isolated" and "angry" for being pushed into reality TV fame at a young age.
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