Secret Heartbreak! Inside Anna Duggar's 'Major' Family Tragedy & Traumas

Mike, a Florida-based missionary, said he and Suzette, 62, withstood a "major tragedy" in their book, published in 2000. "Years ago…we had to bury our baby daughter Joanna. That was a major painful tragedy," he wrote.

Later in the tell-all, Mike, 57, explained that their third child suffered a spinal birth defect. "Several years ago my wife and I had two wonderful children. Then, our third-born child was born with a very serious birth defect, Spina Bifida," he said, adding that the tragedy did not stop them from welcoming more children. "At that time we had to make a decision, should we continue to trust God with the size of our family or should we take matters in our own hands. By God's grace we chose to continue to trust Him and God has since blessed us with five healthy children."

Anna, now 29, nearly became the victim of a terrifying dog attack as a child, Mike also revealed. "One day my daughter Anna was going to the back of our property to feed the animals…Suddenly there appeared two vicious dogs and they started to chase her," he recalled.

He claims she was saved by her faith. "With all her might she cried out, God deliver me from these evil dogs,'" he said. "God heard her cry and they left and she has never seen them again."

Mike survived chronic pain just months before publishing his book. "I got very, very sick. And then it got worse!" he said. "I was so weak for about three months that I did not have the strength to get out of bed without my wife pulling me up."

"I would cry out to God with tears to be healed," he continued, explaining that he was later diagnosed with medical condition Fibromyalgia. He said he was later healed through missionary work and prayer.

Anna is still close with her parents, who live in Interlachen, Florida. But the soon-to-be mother of five's seven siblings don't all still follow a strict Christian way of life.

Anna's older sister Rebekah, 34, got divorced in 2015, which likely upset her fervent Christian parents.