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