On a sunny afternoon in Queens, beneath the orange “Bullpen Gate” arch at Citi Field, MLB and New York Mets employees volunteered to pack 500 “JoyJars” -- mini-gift-care packages -- for pediatric cancer patients.

MLB and Mets employees were all here on Childhood Cancer Awareness Day to partner with with the Jessie Rees Foundation, a pediatric cancer nonprofit, and the Amazin' Mets Foundation to help fulfill this large JoyJar order.

The Jessie Rees Foundation -- also known as NEGU, which stands for Never Ever Give Up -- was founded in 2011 by Jessie Joy Reese and her parents when she was diagnosed with cancer at the age of 11. She passed away the following year, less than 12 months after receiving her diagnosis.

But before she passed away, she and her parents established the foundation, the NEGU slogan and the JoyJar system for young patients battling cancer and their families, who are all in need of support and a network of resources.

More than a decade later, the foundation now works to distribute JoyJars to pediatric hospitals around the nation. The plastic jars are filled with hospital-approved toys, games and activities that are meant to encourage and uplift children going through treatment.

Grant Frum, director of development at the foundation, spoke about partnering with MLB and the Mets to pack these JoyJars and what they do for the young patients who receive them.

“It's our first time stuffing JoyJars in a stadium, which is really special,” he said. “And it’s really special when two organizations can come together like this to help make a huge difference in lots of kids fighting cancer.”

According to the American Childhood Cancer Organization, each year in the U.S. there are more than 15,000 children between the ages of birth and 19 years of age who are diagnosed with cancer, with the average age being just 8 years old.

These JoyJars are small gifts that can brighten a patient and their family's day, especially during some of the darkest times they may go through together.

And no one understands this feeling as much as Todd Lahtinen, an MLB volunteer. In 2017, his daughter, Savannah, was diagnosed with a rare form of bone cancer.

“For me, this event has special meaning, because my daughter Savannah was diagnosed with Metastatic Ewing sarcoma when she was 6 years old,” said Lahtinen. “Usually it's in long bones like femurs and it had spread from her foot to her lungs, so we were in active treatment for over a year with her.”

Savannah is now 12 and has been in remission for more than five years, but her father remembers the difficulty of the treatment and recovery process all too well.

“During that process, it was little moments where nice things would come like JoyJars, where you'd have a break from the intensity of cancer treatment and get to enjoy something sweet and fun and silly and distract from the gravity and weight of the situation that was going on.”

Lahtinen was not the only volunteer with a personal connection and feeling of responsibility to give back at the stuffing event. Daniel Barrueco, who works in MLB operations, is a former pediatric cancer patient himself.

“I was treated when I was younger actually,” he said. “And these sort of jars, these sort of gifts, anything that I would receive, it was absolutely essential for me. And it’s the type of thing that got me through it.”

Barrueco, 25, received his diagnosis when he was 7 and has been in remission for years now, but he still feels the urge to give back to young patients, as others did for him when he went through that treatment.

“It feels like I'm forever indebted to all the people and organizations that would help me,” said Barrueco. “It feels like I'd never be able to fully pay back all of the support that I've gotten, but the best I can do is try.”

Small but powerful acts of service and kindness like packing JoyJars can mean an entire world of difference for a young child who just wants to get better as Barrueco did, as Lahtinen and his daughter did. And especially as Jessie Rees did.

To learn more about events like these and how you can support the fight against childhood cancer, visit MLB Together.