Halloween is a time for siblings to engage in war after a night of trick-or-treating. Battles ensue over who got the most candy. On a good night, a civilized “trade” might take place.

But this year, 11-year-old Ella and her 8-year-old brother Tate were on the same team. While Ella spent her night at Children’s National Hospital, Tate was out doing “double duty” trick-or-treating and making sure his older sister didn’t miss out.

Just days before Oct. 31, Ella Sorrell was “walking funny,” according to dad Bret Sorrell. The 17-year veteran of the Capitol Police was picking his daughter up from school when he noticed “something’s not totally right,” he told HOH.

After a visit with her pediatrician, Bret and his wife Gwen took Ella to a nearby emergency room in Stafford, Va., where doctors recommended transporting her to Children’s National Hospital in Washington.

While there, Ella underwent tests, including an MRI, that would hopefully explain the cause for the abnormal symptoms of a seemingly healthy kid.

On Halloween, MRI results revealed “a mass at the base of Ella’s skull,” according to her mom’s Facebook post, and a subsequent biopsy revealed a parent’s worst nightmare.

Ella was diagnosed with diffuse intrinsic pontine glioma, or DIPG, “an aggressive type of childhood cancerous tumor that forms in the brain stem,” according to health information website Healthline.

“The tumor is currently wrapped around Ella’s spinal cord leaving doctors with little more to do surgically,” reads the GoFundMe page that Sorrell’s colleague, Beth Taylor, created to help the Sorrell family with medical expenses and Ella’s dream trip to Walt Disney World in Florida.

“The goal of this fundraiser is to raise enough money to send Ella and her family on her dream vacation to Disney as well as help with medical expenses, gas, food, and time off from work.”

The fundraiser is roughly $2,700 shy of its $30,000 goal and has seen an outpouring of support and donations, including from Oklahoma Republican Rep. Markwayne Mullin.

Ella, who fearlessly named her tumor “Venom” after the Marvel Comics character, began radiation Wednesday. “She loves arts and crafts, swims for her local community pool, as well as spending time with her mother Gwen, father Bret, and younger brother Tate,” posted Taylor.

Sorrell expressed gratitude for the level of support he’s received from his Capitol Hill police colleagues.

“This exemplifies what we stand for,” he says.

For more information and to donate to Ella’s GoFundMe page, click here.