7-year-old Brock Fleming is like many boys his age, quiet around strangers, loves dinosaurs (especially T-Rex) and would eat candy all day and all night.

But unlike most 7-year-old boys, Brock is fighting for his life. In May, he was diagnosed with Diffuse Intrinsic Pontine Glioma, or DIPG. It's a rare type of terminal pediatric brain cancer.

On May 4, Brock was playing outside when he tripped, fell to the ground and hit his head. He woke up confused. His parents rushed him to the hospital for what they thought was a concussion. Instead, they started on one of the hardest journeys of their lives.

On Saturday, the Flemings got some help from around 350 people who turned out for the first Team Brock Halloween 5K Fun Run at Old Settlers Park in Round Rock.

The Austin Cops for Charities non-profit group hosted the event. Brock's father, James, is an Austin police officer.

"Brock's a pretty strong kid, he's determined. He sets his mind on what he wants to do and he makes sure it happens and he doesn't let anything stop him," said Brock’s mother, Melissa.

The event featured a lot little runners followed by a few big runners followed by even more walkers and strollers. All to support Brock and to find a cure to DIPG.

"It's a very rare type of cancer but our researchers believe if they have the funding to do the research for this specific cancer, it can unlock the homerun cure and that means they can actually go after markers that are in all cancers," said John Branham with The Cure Starts Now Foundation, a non-profit research group.

The huge turnout was a blessing to the Flemings.

"I couldn't believe how many sponsors came out to show their support and how many people signed up. It's incredible," said Fleming.

The 7-year-old who loves Batman is proving he's the superhero in this community.

DIPG is a disease which strikes at the heart of childhood and it is a disease with no cure. It affects the pons portion of the brainstem, rendering nervous system function impossible. Symptoms include double vision, inability to close the eyelids completely, dropping one side of the face and difficulty chewing and swallowing. Unfortunately these symptoms usually worsen rapidly because the tumor is rapidly growing.