The pair collaborated on her album Loose in 2006, which became a worldwide smash, selling 12 million copies and spawning two number ones – “Promiscuous” and “Say it Right.”
They followed it up with 2009’s Mi Plan, a Spanish-language album that went platinum and won a Latin Grammy for best female pop vocal. “We’ve done well as a team,” Castellon admits.
But Furtado, 35, tells PEOPLE that working with a spouse is not always an easy process.
“It’s a healthy tension working together,” she says. “It doesn’t always go smoothly, of course, and it can be really challenging when there are differences of opinion, which of course happens. But good things always tend to come out of it, and that’s the whole point.”
“We make it work because he’s often doing his own thing,” Furtado continues. (In 2013, he recorded and mixed Jay Z’s Magna Carta Holy Grail and Madonna’s MDNA World Tour DVD.) “I go off and do my own thing, so it’s not like we’re working together all the time.”
Furtado, who was in Orlando on Friday to induct her husband into the Full Sail University Hall of Fame, plans to return to the studio this year. “When we work together, he challenges me,” she says. “That’s what makes him so great in the studio. If it were an easy process, the final product wouldn’t be very good, but he helps me to reach a little bit further. He pushes my boundaries.”
What about their personal lives? Furtado has a 10-year-old daughter, Nevis, from a previous relationship, and has no plans for more children. “We’re very blessed to have a beautiful family,” says Furtado. “We have a great life together. Life is good.”