The cousins are seniors at Menlo-Atherton High School, near Palo Alto. Tautuaa looks like the kind of guy who would bury you in a bear hug; he plays football and has a big smile. Fifita is shorter and speaks softly, except when egged on by his cousin.
The cousins consider themselves more like brothers.
They were both born in the United States, but they grew up in Tonga. Tautuaa talks about how Fifita helped him acclimate to the island when he first moved there, and how when Fifita can't think of the right word in English, Tautuaa often translates for him.
"No matter if there's trouble, he always steps up for me," Fifita says proudly. "And I always step up for him."
And they've been singing and playing music for as long as they can remember.
In Tonga, they attended Tupou College in Toloa and joined the choir in the Free Wesleyan Church of Tonga.
Tautuaa says singing in the church choir taught them everything they know about melodies and harmonies.
"The kids, we sit in the front and then on the row next to us are all the men. And when we listen to them harmonize ... it clicks," he explains.
"And listening to them is like a dictionary for us. It’s like we define every single note when we’re young, and just build on it as we get older."
In addition to singing hymns at church, the two spend a lot of time making beats and writing their own songs.
"We mostly talk about, you know, life ... just like reading a story," Fifita says of their original songs, which are usually him rapping over Tautuaa beat-boxing.
"Talking about growing up in a poor family and stuff like that, and how we got here in America, life and education."
It's clear that to them music isn't just an extracurricular activity. They say it makes them better people, better athletes, better students, better friends. And it also keeps them safe.
"I think music definitely helps us not do the bad stuff ... it keeps us off the streets," Tautuaa reflects. "It separates us from all the other, you know, drugs, shootings, massive chaos ... it just humbles us."
Fifita agrees: "Music is like a spirit that comes through my mind, and it gives me good ideas. It helps me a lot."
So where do they see themselves in five years?
They toss around some ideas: setting up their own music studio, playing college football for Tautuaa, joining the Marines for Fifita.
But one thing is certain: Wherever they are, they'll be singing.