Asher Rock is a lively 1-year-old boy who loves blowing kisses and playing with his “Percy the Small Engine” model train.

Asher has been a different boy, his mother said, since ending chemotherapy in February.

“It’s like I’m beginning to get to know him as a completely different child since February,” Josie Rock said. “It’s amazing to me how chemo affects children — it takes so much away from them. Now that he is off chemo, he is happy and has so much more energy.

“He is a completely different child.”

Asher Rock was diagnosed at 4 months old with childhood retinoblastoma, a rare form of eye cancer. Though he finished chemotherapy in February, his treatment is far from over.

“We are waiting for another MRI, which of course gives me that ‘scanxiety’ about what’s going on behind the eye,” Josie Rock said. “Hopefully nothing is going on, but with retinoblastoma being as aggressive as it is, it can easily spread.”

Friends of the Rock family are organizing a benefit to help cover some of the costs of Asher’s treatment.

The Outrun Cancer 5K and Fun Run will be at 4 p.m. Sunday at the Martha Hope Cabin at 528 Prior St. NE in Gainesville. Registration, which begins at 3 p.m., costs $30 for the 5K and $15 for the one-mile fun run.

Josie Rock said she can’t imagine the financial strain she and her husband, Marcus Rock, would feel, if not for the charitable fund helping them.

“If that were the case, we would probably be out of a house right now,” she said.

Josie and Marcus Rock also have two daughters, Campbell, 7, and Hallie, 3, and Josie Rock is just finishing nursing school. But the biggest difficulty in affording Asher’s treatment is the Rocks “never know what to expect.”

“He finished his chemo in February and now we’re just focusing on aggressive laser, because he has had more tumors pop up,” she said. “Last month, there was between 15-20 new tumors in his eye, and that was with chemo being done. So we just never know, and the costs just vary depending on what happens.”

C.J. Greene, a high school friend of Josie Rock, said she and her cousin Rebekah Rico wanted to help with the costs of Asher’s treatment.

“We just both felt really like the Lord was leading us to help their family,” Greene said. “We kind of polled some of her friends to see who would come on board to try to organize and raise as much money and awareness as we could. We prayed about what we could do for them, and that’s how the 5K came about.”

Josie Rock said the surgeon at Children’s Hospital of Atlanta at Egleston warned them to expect more tumors to pop up in Asher’s right eye.

“The surgeon said, with chemo being over and his tumor being as aggressive as it was, to expect more tumors to pop up, which is what’s been happening,” Josie Rock said. “We just didn’t expect 15-20 tumors to pop up. So we just have to keep at it, and stay on top of it with the laser.”

Asher is looking at years of MRIs, monthly eye exams and other preventative measures.

“He still has a good chance of keeping his eye, but he could still lose it, depending on how these tumors remain,” she said. “But we’ll just keep up treatment … and we’ll go from there.”

Josie Rock said Asher is doing well, all things considered. He crawls and scoots through his home, pulling up on the furniture to play with the two family cats. He calls for his “Dada” Marcus, makes silly faces at his mother and giggles while he tosses plastic blocks.

“He is a joy,” Josie Rock said.