A 3-year-old girl with cancer has melted hearts online by reuniting with her brother after nine days in isolation.

In a clip on TikTok posted by her parents Jen and Mike Clark (@supertiredparents), Abby sits in her hospital bed, waiting for her soon-to-be 6-year-old brother.

As he walks in the room, Abby’s face lights up and she reaches out eagerly for a hug.

The couple, from Texas, told Newsweek that the siblings are inseparable. “They sing, play, and just adore each other,” Jen said. “He’s her biggest supporter, always cheering her on, and they both miss each other so much when she’s in the hospital.”

The two children were separated for nine agonizing days while Abby remained in isolation due to severe health complications.

Mom Jen explained that the family’s ordeal began in August when Abby was diagnosed with B-cell acute lymphoblastic leukemia (ALL).

“It completely blindsided us. There were no warning signs, and suddenly we were thrust into this long and difficult fight,” she said. “Her treatment plan will last about two and a half years, and we’re taking it one day at a time.”

The nine-day separation between Abby and Connor was triggered by a severe drop in Abby’s immune system due to chemotherapy.

“At this stage of treatment, the chemotherapy is incredibly tough on her body,” Jen explained. “Her blood counts drop to dangerously low levels, leaving her unable to fight off even the smallest infection. That’s what led to her becoming septic with both E. coli and klebsiella. It’s terrifying as a mom.”

The clip has touched millions online, amassing 9.8 million views on TikTok alone. Users on the platform rallied around the family, sending their prayers and well-wishes.

“Nothing like the comfort of being back with your brother,” the account behind The Leukemia & Lymphoma Society commented.

“Crying, cancer mom here too. When siblings reunite, ugh the sweetest,” another user wrote.

Jen and Mike initially began sharing Abby’s journey on TikTok as a way to keep family and friends updated, but the raw and emotional clips have since gained a much larger audience.

“It’s helping raise awareness about what families like ours go through, and I hope it encourages more people to donate blood,” Jen said.

Beyond the touching reunion, the parents hope the videos help raise awareness about childhood cancer and the critical importance of blood donations. “Blood donations have played a huge role in keeping Abby alive,” Jen added.

For now, the family is celebrating small victories. Abby has been stable enough to return home this week, though her battle is far from over.

“The hope is that her blood counts will continue to recover so that we can resume her chemotherapy in about 10 days. Right now, we’re on pause to let her body heal from the infections,” Jen explained.