Parents find touching note from dead son

Amber Shoemake admits to being an overprotective mom.

After struggling to have a baby, she finally got her miracle, a healthy baby boy named Leland.

"He was smart from day one," Shoemake told CBS News, explaining how he knew his ABC's, numbers, colors, shapes by the time he was 1-year-old. Six years later, it's no surprise that the word people used to describe him was "intelligent."

Leland loved school, learning about World War II, quoting Adam Sandler movies -- and the one thing he loved most: playing in dirt.

"I never imagined that would be the thing that would take him from me," Shoemake said.

The 6-year-old contracted Balamuthia mandrillaris, a rare amoeba that causes an infection of the brain and spinal cord, which was likely caused by something in the dirt.

Last month, Leland started complaining about headaches. Shoemake took him to a pediatrician in Williamson, Georgia, where he was treated for allergies.

Over Labor Day weekend, his condition worsened; he started vomiting and was taken to a local hospital. A CT scan showed swelling behind his nasal cavity, which doctors believed was due to a sinus infection.

Despite medication, Leland's health continued to decline.

Every day, Shoemake sat by her son's bedside trying to figure out what was wrong.

After numerous CT scans and a spinal tap that showed inflammation, Shoemake asked doctors to check for the one thing they hadn't yet -- a parasite, specifically an amoeba. The next day, she got her answer.

"My boy was so extraordinary that of course it had to be something rare," Shoemake said.

Two days after he started treatment for the parasite, he became unresponsive and brain dead.

"They repeated the brain death test 12 hours later and confirmed our worst fear," Shoemake said. "They came in and took him off the ventilator and I watched my baby leave this world."

When Shoemake and her husband, Tim, returned home to pick out his burial clothes, they spotted a piece of notebook paper sitting on a table that gave them a sign of hope.

It was a note from Leland: "Still with you; thank you mom and dad; love mom and dad; it's a good day."

"We have no idea when he wrote it," Shoemake said, describing how she broke down and cried after reading it. "But you can tell he was always a special child."

Today, his parents will hold on to the comfort found in that note as they pick out a headstone.

"He was the light of our life and the center of this family," Shoemake said. "I count the days until I can see his sweet face again and hear that beautiful voice."

Until then, she silently tells Leland: "Sleep tight and don't let the bed bugs bite!"