Twenty-one-month-old Ryan Roberts has only a few weeks left to live, and his mom, Diane, has only one request -- she wants other parents to see their children smile.

According to NBC, Ryan was born with Down syndrome and a congenital heart defect. During a recent surgery, doctors told Diane and her husband, Erik, that there was nothing else they could do for their son's heart. The couple then made a painful decision to stop Ryan's supportive care and sign a DNR, HLN TV reports.

Like the Rapinis and the Canahuatis, parents who also faced the unimaginable grief of learning that a child won't live, the Roberts family created a bucket list to help everyone involved get through this difficult time. To date, Ryan has pet a puppy, played with finger paints, gotten a speeding ticket in the hallway of the hospital and even drank a (root) beer with dad on his 21st (month) birthday.

When friends and family began to ask Diane and Erik how they could help and what they could do, they would say that they didn't want anything.

“I said, just go create a memory with your kids. Just go put a banana split down in front of your kids for dinner and watch their faces light up. No chicken, rice and broccoli tonight, just ice cream. They're going to remember that forever,” Diane told HLN TV. "Watch them smile."

Soon, Diane's friend Melissa Neidhardt kicked off "Ryan's Banana Split Party". She invited fellow parents via Facebook, asking everyone to help fulfill Diane's wish. Neidhardt wrote on the page for the event:

I am throwing Ryan his very own Banana Split Party. Although he will not be able to have one, I thought it would nice if we could all have one for him, whether you have children or not. So some night for dinner, have just a banana split but take a picture and post it to Facebook event page so they can see all the people that are fullfilling their wish!!! So who cares if your children don't get their veggies one night for dinner, allow them to "break the rules" for just one night and think of a special little boy while you're doing it!!

Melissa initially invited 200 friends, HLN TV reports. As of June 20, only two weeks later, almost 300,000 Facebook invites have gone out and more than 25,000 Facebook users are "attending." Families from all over the world have posted photos of their own ice cream parties with supportive messages for the family. Grieving mothers and fathers have even shared their own stories of loss.

This effort is just one example this week of the tremendous ability that social media has to bring communities together when families need support. In Texas, a 4-year-old with terminal cancer, Dyrk Burcie, has inspired a similar movement. Firefighters who work alongside Dyrk's father, Dameon, organized a photo shoot to spell out the boy's name in fire. Other departments caught on and arranged similar photos with creative messages. Now, Dyrk's Facebook page houses dozens of pictures of fire departments, sports teams and community members all dedicated to Dyrk.

In a recent interview, Dameon said that, "In a horrible situation like this, it's nice to see that it is bringing people together, bringing communities closer together ... At least something positive can come out of it." Diane Roberts agrees. In response to the exponential growth of Ryan's Facebook event, "It's crazy," she said.

To add your own photo to Ryan's Banana Split Party, click over to Facebook.

LOOK: Photos from Ryan's Banana Split Party