people s days after her worst day. a fourth child, liam, a preemie, died at just six weeks. i felt like my son can t just come in this world just to suffer and then die. reporter: you found his purpose. and it s helped so many kids. reporter: how many good deeds has your group done? hundreds. reporter: hundred? maddie started a nonprofit called liam changed the world and in the 10 years since, he has. we ve paid medical bills for children. reporter: from planning a parade for a kid with cancer, to collecting supplies for flood victims. if kindness is needed, liam s mom is there. her most recent effort: to help army private first class harmony jackson surprise her family. i love you. reporter: harmony hadn t seen her kids in person. i said i love you! reporter: .in seven months. maddie found harmony on facebook and offered to orchestrate the reunion. she lured the dad, telling him