And that was the easy part of his childhood. When his mother died, he was sent to the Amazon jungle to live with his aunt.
"She helped me a lot but living in the jungle is not easy," he said. "You have to get food, you have to fish, you have to go hunt.
"But I learned a lot of things."
Fernandes' mixed martial arts journey has already netted him the Dream bantamweight and featherweight titles.
And on Oct. 18 he looks to upgrade his One FC bantamweight interim title into the real thing when he takes on title-holder Soo Chul Kim (7-4) at "One FC: Total Domination" at the 12,000-seat Singapore Indoor Stadium.
Fernandes won the interim 135-pound title in May via decision over Koetsu Okazaki at "One FC 9 — Rise to Power" while the 21-year-old Kim was sidelined by injury.
Their Oct. 18 showdown will decide the undisputed champion.
Kim defeated Leandro Issa by TKO at "One FC 6 — Rise of Kings" in October 2012 to become the first One FC bantamweight champion.
If Fernandes wins, he's bringing the title back to Vancouver. That's where the 33-year-old Brazilian now calls home.
Fernandes was at a jiu-jitsu competition in California some 10 years ago when he was invited to come north and train.
He liked what he saw and stayed. He met his wife here and they now have three boys — one, two and seven.
"Today I have everything there — my family, my kids there."
He trains full time although he does some seminars and private lessons.
The 33-year-old Fernandes, who normally weighs around 147-148 pounds, divides his training time between Marcus Soares Brazilian Jiu-Jitsu in Vancouver and the Mamba Martial Arts Academy in Abbotsford.
For Kim, he travelled south to Kirkland, Wash., to train with Matt Hume at AMC Martial Arts.
Fernandes has won six in a row and 13 of his last 14 fights, with the lone blemish a decision loss to Hiroyuki Takaya in December 2010. His other two losses were in 2006 and 2007 after he opened his career with a win.
After that 1-2 start, he got back on the winning track with a pair of 2008 wins on cards in Calgary. A year later he won the Dream featherweight (145-pound) title.
Fernandes started learning jiu-jitsu at 14 in Brazil. At the time he was selling ice cream and cleaning houses to get by.
He and a friend noticed a jiu-jitsu school in the neighbourhood and he started watching what went on inside. Fernandes didn't have the money for lessons but the mother of a friend said she would pay for both.
Fernandes was a quick learner and soon won two tournaments. But the money for the lessons dried up. The 15-year-old gave the bad news to his coach, who agreed to keep teaching him if he cleaned the gym.
"I worked for my training," he said.
Fernandes did so for three to four years. Then his coach told him to stop cleaning and focus his training on becoming a world champion.
"And I did," he said.
Fernandes went on to win Brazilian and Pan-Am jiu-jitsu titles. Then he switched his focus on MMA, with a string of wins following a bumpy start.
"I have the focus, I have the discipline," he said, by way of explaining his success.
Fernandes made his One FC debut in Manila at "One FC 5 — Pride of a Nation" in August 2012, defeating Gustavo Falciroli before submitting Yoshiro Maeda on a Dream card in Japan last December.
He joined the Singapore-based promotion after being linked to the UFC.
Fernandes looks back at his life to date and sees not the hardships, but a long list of people he has to thank for helping him along the way.
"Be thankful for what you have," he counsels.
He should know.