A mother and father who lost their daughter one year ago are asking the world to follow a set of rules she had written down before she died.

On Jan. 28, 2020, Ellie Pruitt suddenly became sick at school. When her health wasn't improving, she was admitted to Children's Hospital of Atlanta, where tests revealed she had autoimmune diseases, including Lupus, which were attacking her blood cells.

Ellie died days later on Feb. 6, 2020. She was 8 years old.

"She was extremely smart. She was just so kind to everyone and she knew how to connect with people," mom Heather Pruitt of Woodstock, Georgia, told "Good Morning America." "She was helpful, she was thoughtful, she was a very special little girl."

"Everything about her we'll miss," dad Chuck Pruitt added. "And her brother, of course, he will miss her."

Ellie's parents said she was diagnosed with juvenile arthritis at 4 years old.

Children's told "GMA" there's no indication that the autoimmune diseases were brought on by Ellie's juvenile arthritis, though juvenile arthritis is an autoimmune disease itself, so her immune system was already compromised and more susceptible to other illnesses.

"It was nowhere on our radar that this could've even happened," Heather Pruitt said.

"The second night [at Children's] she had a blood transfusion," she added. "Her blood cell count and hemoglobin were extremely low. She went into cardiac arrest; they stabilized her heart and lungs. ... At that point, they said, 'We've never seen anything happen this quickly.' They told us they did everything they could do to stabilize her.'"

When they came home from the hospital, the Pruitts found a list that Ellie had secured to her bedroom door before she died.

It read:

1. Have fun
2. No fighting
3. No pushing, shoving or hitting
4. Always love.

"That night it just caught our attention," Heather Pruitt said.

The Pruitts' congregation of Woodstock City Church made cards with Ellie's photo featuring her rules on the back.

Soon, Ellie's rules were also seen on display at neighborhood businesses, schools and fast food restaurants.

Children's also shared the list on its Facebook page, explaining how Ellie inspired people to participate in the "Connect with Kindness" campaign through its hospital.

"One year ago this month, the Queen of Kindness, 8-year-old Ellie Pruitt, gained her angel wings after a lifelong battle with autoimmune diseases," Children's wrote in the caption, adding that it's asking others to spread kindness in memory of Ellie.

"Whether it’s simply holding the door for a stranger, sending a note to an old friend or completing a random act of kindness for your neighbor, join us as we reconnect, inspire and challenge one another to connect with kindness," the hospital added.

The Pruitts said the movement has helped them through the tragedy of losing their daughter.

"Everybody can do these things every day," Chuck Pruitt said of Ellie's rules. "It's a simple thing that can change the world."

In addition to her kind-hearted ways, Ellie's parents said she'll be remembered for her love of dance and the special bond she shared with her 5-year-old brother, Luke.

To get involved int he Connect with Kindness campaign, visit CHOA.org/kindness, perform a good deed, then challenge friends to do the same. Share it on social media using #KindnessATL.