Since Zayn Malik left the group in March, the remaining members – Harry Styles, Niall Horan, Liam Payne and Louis Tomlinson – have been dogged by rumors they'll split.
Not the case.
"The boys know that by sticking together they can still pursue everything they want to do as a foursome, as well as individually," a friend tells PEOPLE. "And there's no reason why they can't have lifetime careers both as a group and working on their own solo projects – just like the Stones."
The veteran performers have, of course, remained a band for 50-plus years, despite pursuing side projects. Adds the 1D friend: "The Stones are a huge inspiration for the whole group, and they are huge fans."
So what's next for 1D's next solo moves? Styles, 21, is reportedly planning an eventual foray into acting. Meanwhile, Tomlinson, 23, has launched his own record label, an imprint of One Direction creator Simon Cowell's label Syco.
"It's the best of all worlds. The band all have their own solo interests, whether it be music, art or acting, but they can stick together," adds the friend. "Harry, Louis, Liam and Niall are all very loyal to each other and support each other's future together and on solo projects – music or otherwise … They are all incredibly loyal despite the multiple offers they get all the time.”
As for One Direction's future: The band mates – who re-signed their recording deal with Cowell and his Syco Music label a couple years ago – are about to kick off the next leg of their On the Road Again world tour and are working on their fifth album.
RELATED VIDEO: Zayn Malik on Leaving One Direction: 'I Feel like I've Let the Fans Down, but I Can't Do This Anymore'