Even as she struggled through painful cancer and aggressive treatment, Kayla Rush, 11, worried about others around her.

She was diagnosed in spring 2008 with osteosarcoma, an aggressive type of bone cancer, and in July 2008 her right leg was amputated above the knee.

Two days after the surgery, another little girl who had injured her jaw arrived to share Kayla's hospital room at Children's Hospital of Pittsburgh, and Kayla's concern immediately turned to her, said Dawn Rush, Kayla's mother.

Kayla's struggle with cancer persisted, and over the last few weeks she was at the University of Texas MD Anderson Cancer Center in Houston, awaiting a trial drug and undergoing radiation while tumors spread rapidly to her spine, shoulder, ribs, knees, ankles and forehead.

Sitting in her daughter's room last week, Mrs. Rush said she started crying, and told Kayla it was because she could see how much her daughter was suffering.

"She said, 'Don't worry, Mommy. I'm OK,' " Mrs. Rush said.

Kayla died Thursday in Houston before she could receive the trial drug.

"That morning, she looked at me and said, 'Mommy, I'm ready to go to heaven,' " Mrs. Rush said.

Kayla Rush, born Aug. 6, 1999, was the first-born of Dawn and Jim Rush of Pleasant Hills. She had one younger brother, Nicholas, 5.

She loved climbing trees, riding her bike, going to friends' houses and swimming and fishing with her grandparents. She especially loved animals, said her grandmother, JoAnne Rush of Pleasant Hills, and played with her family's cats, dog and guinea pig.

"She was a very sociable, very friendly little girl," JoAnne Rush said.

Her parents noticed she was limping in April 2008, so they took her to a doctor, thinking she had sprained her leg. They discovered, instead, that she had osteosarcoma.

Kayla, who would have been a sixth-grader at McClellan Elementary this year, was in and out of school over the last two years as she underwent various cancer treatments. She went through chemotherapy and radiation, but in June 2009, a scan revealed 25 tumors in her lungs.

She had surgery to remove the tumors, and when she was well enough to fly, her parents took her down to MD Anderson Cancer Center to see doctors who specialized in osteosarcoma.

But Kayla's condition continued to deteriorate. On July 13, her family made a third trip to the Houston center, hoping to receive a trial drug. While they waited, friends and neighbors back in Pleasant Hills raised money for the family.

Members of "Team Kayla" ran in the 5K race that began Pleasant Hills Community Day last week and raised $1,515. Other community events have also been held to support the family since June, said neighbor Diane Campano, whose daughter, Megan, was a friend of Kayla's.

Kayla died less than two weeks after her 11th birthday.

"She was the strongest, bravest girl, and definitely my hero and my inspiration," Dawn Rush said. "She was my whole world."

Funeral arrangements through Jefferson Memorial Funeral Home in Pleasant Hills are pending.

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