Worthy and her sister Kalista have gotten millions of views and likes on their videos on the popular app

Kalista Hesch and her 11-year-old sister, Worthy Rigelsky, have an unbreakable bond.

The duo has taken social media by storm thanks to their fun videos, which feature them dancing and having fun around their home in Wisconsin.

"Worthy is, if I could describe her in one word, she's just 'pure joy,' that's always the first word that comes to mind," Kalista tells PEOPLE (the TV Show!) of her sister, who was adopted from China six years ago by their parents.

"She definitely has her moments, she's human too so she's not always 100 percent happy, but I would say 99 percent of the time she's always just pure joy and just happy."

"She's a little spunky one, she's high energy," she adds of Worthy. "She's like the sweetest thing ever but she definitely has a sassy side."

But Worthy has also been showing off her hairstyling and makeup skills to an audience of millions on TikTok, and she often uses Kalista as a model.

kalista and worthy
Worthy and Kalista Hesch
| Credit: worthyandkal/tiktok

"She's just like a little perfectionist and she's just always been, like I said she's just pure love, so she just loves touching, she's just so lovable, and when anyone comes over she just grabs a hairbrush and immediately starts brushing their hair," Kalista says of her sister.

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Worthy was born with Down syndrome — a genetic disorder that causes intellectual disabilities and developmental delays. Kalista says they began to grow close with each other over recent years, and it was during a sleepover that they discovered their mutual love for TikTok.

"I put on a song and she was just standing behind me and she was just fixing my shirt and adjusting my necklace and went like this to my hair and everyone just flipped out," Kalista recalls. "She's just such a little perfectionist, she just wants to fix you up and make sure everything's okay and every little detail's perfect."

"Worthy literally means the world to me," she adds. "Every day that I come over to my parents' and see her big smile, I'm just so grateful to have her in my life... I don't know what I would do without her."

Aside from TikTok, you can also find the two on their Instagram pages.

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