Best grandpa! Matt Roloff loves being a grandfather to his son Zach Roloff's son Jackson , and the Little People, Big World star even put all his years of planning birthday parties for his own kids to use by throwing Jackson a party to celebrate his first birthday. Judging from the photos on Instagram, baby J had a blast at his camping-theme party — but it looks like grandma Amy Roloff didn't get an invite.

"Getting everything ready for this little farmer's one year birthday celebration tomorrow…" Matt teased the day before the party, which took place on Saturday, May 12. It looks like Matt was the one who prepped the decor for the party, which looked like it took place on Roloff Farms, and Grandpa Matt must have been busy setting up camping tents to go with the party's theme.

In an adorable shot taken during the bash, Matt held baby J as he held onto a plastic frisbee. In the background, a tent was decorated with a pennant banner that read Camp Jackson. "Happy Birthday baby J. What an incredible day of celebrating your [first] year of life!" Matt wrote in the caption.

Jackson's mama — and Zach's wife Tori — also shared an adorable photo from the party on her Instagram. Baby J sat shirtless in his high chair as his parents posed behind him with a small, naked cake sitting on his tray. It looked like it was meant to be a smash cake, but baby J only had a tiny mess of frosting on his face as the rest of the cake seemed to be in tact. "And somehow we have a one year old? Happy birthday Mister Mister. We love you more than you will ever know," Tori wrote in the caption.

But judging from the social media posts that were shared from the party, Jackson's grandma — and Matt's ex-wife — was not in attendance. She did not come up in the photo Matt shared, and she didn't make an appearance in Tori's feed or her Instagram story.

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