Eight years later, Colton Burpo told MSNBC the memories of seeing his family members in heaven are still vivid.
"I think those memories of heaven are implanted," Colton, now 12 years old, said on the Today show Tuesday, where he was joined by his parents.
"The things I remember most are my family members and Jesus."
After suffering a burst appendix and undergoing several surgeries in 2003, Colton told the Burpos during his time in the hospital he actually visited heaven. The Rev. Burpo recounted in the 2010 book that when asked if he remembered the hospital, the boy, then 6, said "Yes, Mommy, I remember. That's where the angels sang to me."
He described meeting a great-grandfather he never met and visiting the Burpo's miscarried daughter, whom the Burpos never told him about, Sonja Burpo told MSNBC.
"We questioned our son at first," the Rev. Burpo said. "I think as parents everyone can tell when their 4-year-old is telling the truth. When they're telling you things they cannot make up."
The new book, Heaven Is for Real for Kids, was released Nov. 8. Colton said the 32-page picture book is for ages 4 through 8.
"It works for them pretty good because the wording is easy [and] pictures describe the story," Colton said.
Both books are available at local bookstores and on major online bookstores. A movie of Colton's experience is in the works.
"God bless the story. … A lot of people have found different parts in it that felt their hearts and are touched by it," Sonja Burpo said. "Our intention was to just write and help a few people and it just kind of exploded."