"I think we started off with 80 people last Saturday, and as of today, there's almost 500 that have joined the page," said Jayme Gudde, Erin Hook's cousin.
Erin, the daughter of Buchanan County Commissioner Ron Hook, died in a car accident earlier this month.
Sunday would have been her 21st birthday, and her family wanted to do something special.
"She always loved birthdays. So, this is one thing we could do to honor her in her memory," said Gudde.
The Facebook group allowed people from all over to share their random acts of kindness.
"Orphanages having donations made in Guatemala, there's been people sponsored to go on mission trips to Africa, there's been people who have paid for someone else's coffee," said Gudde.
Their goal was to get 21 people to do one nice thing in a week, but numbers exceeded their expectations.
"As of today, and as we're speaking, there's still even more being posted. We have 161 [people] so far," said Mark Babcock, Erin's uncle.
Family members described Erin as energetic, kind, and full of life.
They said the Facebook group shows how she changed people's lives.
"They're thinking, 'what would Erin do in this situation? What can I do to honor Erin,'" said Babcock.
"Every act is just showing, you know, the love that Erin had because she loved to serve people," said Gudde.
Gudde put together 70 pages of kind acts to give to Erin's parents. She said it is a symbol of life, love, and a way to fulfill Erin's mission.
"February, on Twitter, she posted to live life with a purpose. Find that purpose and hold on to it for the rest of your life. So, we're going to live with a purpose for her," she said.
The family will keep the Facebook page up and running to remind people the importance of paying it forward.