Tori Roloff celebrates son: 'Jackson is three months old!'

Aug. 15 (UPI) -- New mom Tori Roloff celebrated three months with son Jackson over the weekend.

The 26-year-old reality star gave an update on Jackson, her son with Little People, Big World star Zach Roloff, after announcing the infant has dwarfism.

"Jackson is 3 months old!" Tori captioned a photo of her baby boy. "Baby J is so smiley these days! he loves having his hands in his mouth. Bath time is still our favorite time. We're up to 14 pounds! We've decided sleeping isn't totally our thing."

"Jackson is reaching for things," she added. "He is also a professional hair grabber. Baby J has also been moving and stretching like crazy! Keep growing little man! Mom and Dad love you! #zandtpartyofthree."

Tori and Zach welcomed Jackson in May, and later confirmed their son has achondroplasia. Zach and his parents, Matt and Amy Roloff, also have dwarfism and stand under 4'3" tall, while Zach's siblings and Tori are of average height.

"The world is changing. People are more open to diversity," Zach told People magazine. "Whatever he wants to do, we're going to find a way to help him do it. That's our job in life now."

"[Dwarfism is] part of the whole package of who he is," he added. "He's happy and healthy. That's all that matters."

Zach spent the weekend at the 2017 World Dwarf Games in Guelph, Canada. Tori shared photos Saturday of herself and Jackson cheering on the star from home as he competed with the U.S. soccer team.

"Even though we can't be in Guelph doesn't mean we can't cheer on our favorite soccer player!!" she wrote. "Go daddy go!! #wdg2017 #worlddwarfgames2017 #storyofzachandtori."