Blake Shelton on the Balance of Being Both a 'Buddy' and Parental Figure to Gwen Stefani's Sons

Gwen Stefani is mom to sons Apollo, 6, Zuma, 11, and Kingston, 14, with ex Gavin Rossdale

Blake Shelton with Gwen Stefani and her sons Kingston (L) and Zuma. Photo: Gwen Stefani/Instagram

Blake Shelton takes his role as a parental figure to Gwen Stefani's kids very seriously.

The country singer, 44, called in to the Today show on Friday to discuss his new romantic duet with Stefani, "Happy Anywhere," and opened up about the balance of being both a friend and a role model to his girlfriend's three sons: Apollo Bowie Flynn, 6, Zuma Nesta Rock, 12 next month, and Kingston James McGregor, 14.

"That's a scary moment for me because it's one thing for me to be with the kids all the time and be their buddy, but you do have to consider after a while that they start to listen to things that you say. There's a lot of responsibility that comes with that," Shelton said, referring to his sweet Father's Day tribute from Stefani, 50, last month.

The No Doubt singer (who shares her sons with ex Gavin Rossdale) shared a collection of images to her Instagram feed of her boyfriend spending time with all three boys over the years.

"Happy father’s day @blakeshelton thank u for helping me raise these boys!! #weloveyou! G❤️K❤️Z❤️A gx," Stefani wrote in the post's caption.

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Blake Shelton with Gwen Stefani's son Apollo. Gwen Stefani/Instagram

Blake Shelton with Gwen Stefani's sons Kingston (L) and Zuma. Gwen Stefani/Instagram

While social distancing together on Shelton's ranch in Oklahoma amid the coronavirus pandemic, Shelton, Stefani, Apollo, Zuma and Kingston have spent time "doing things that I wished I had time to do for the last 20 years."

"That's literally stupid things, like pick blackberries," Shelton told Hoda Kotb and Carson Daly. "We grew a garden, grew several acres of sweet corn."

"Happy Anywhere," which dropped Friday (along with an accompanying music video, shot in Oklahoma by the "Cool" singer's brother Todd Stefani), is Shelton and Stefani's fourth duet together and first since their hit January duet "Nobody But You."

The romantic new tune sees the pair croon about being perfectly content no matter where they are, as long as they have each other.

Blake Shelton and Gwen Stefani. Warner Music Nashville

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In an exclusive conversation with PEOPLE surrounding the release, The Voice coach said the song reflects how he's been feeling with his rocker girlfriend amid the pandemic.

"An Okie boy and a California girl look on paper like an unlikely match, but what matters is she's a great human being," Shelton raved of Stefani. "She is the most understanding, kindhearted person I've ever met and I learn something from her every day."

Over the last few months, the couple have been holed up in Shelton's cherished Tishomingo ranch — and they've been taking advantage of a little more free time in their schedules.

"The simple pleasure of being together in one place for an extended period of time has been a real gift," Shelton told PEOPLE. "We cook, we clean, we ride four-wheelers and we just enjoy being with each other and with family."