The Hanson Brothers Laugh About Having 13 Kids Among Them: 'They're Really, Really Close'

Issac Hanson, Taylor Hanson and Zac Hanson have a strong bond, having spent over 25 years together playing in their band Hanson and even longer as brothers.

So it should come as no surprise to hear that the 13 kids the threesome have among them are also tight.

"It's a cool thing," Zac, 33, revealed on Monday's episode of the U.K. daytime chat program Lorraine, ahead of their show later that night in Birmingham, England.

"We spend a lot of time together touring, in the studio and around each other, so our kids know each other really, really well," he explained to host Lorraine Kelly. "They're really, really close."

Want all the latest pregnancy and birth announcements, plus celebrity mom blogs? Click here to get those and more in the PEOPLE Parents newsletter.

RELATED GALLERY: MMM-Tots! Your Guide to The Ever-Growing Hanson Family Tree

Though he's the middle child of the brothers (who are the oldest of seven children), Taylor, 35, was the first band member to say, "I do," marrying wife Natalie Bryant in an intimate ceremony at a small chapel in Georgia in 2002.

They've since stayed busy with six kids, including sons Claude Indiana Emmanuel, 6 weeks, Viggo Moriah, 10, River Samuel, 12, and Jordan Ezra, 16, plus daughters Wilhelmina "Willa" Jane, 6, and Penelope "Penny" Anne, 13.

The youngest Hanson member, Zac, married his longtime love Kate Tucker in June 2006 after five years of dating. Together, they have four children: Mary Lucille Diana, 2½, George Abraham Walker, 5, Junia Rosa Ruth, 8, and John Ira Shepherd, 10.

Oldest brother Isaac, 38, was the last of the musical trio to wed. He married Nicole Dufresne in Tulsa, Oklahoma, in October 2006. They have three kids: daughter Nina Odette, 4½, plus sons James Monroe, 10, and Clarke Everett, 11.

RELATED: Go on Tour with Hanson and Their Kids

Back in November, Taylor opened up to PEOPLE about their latest album, String Theory — which saw them adding symphonic arrangements to a sea of songs from their catalog of hits.

Alongside more famous tracks like "MMMBop" and "Where's the Love," the album and accompanying tour included less-oft-performed ones like "Yearbook," "Me Myself and I" and "Broken Angel," as well as new songs like "Reaching for the Sky" and "Siren Call."

The record wouldn't just be a special chapter in the band's book, Taylor hoped. He also wished it would help them get out the same message they've been projecting since day one: They are here to stay, and will never be finished pushing their musical boundaries.

"Part of our story is what has been shared by people who have followed us and stuck with us through the seasons, and I hope what [fans] take away is we're still looking forward and we're proud of where we've been," he said. "The takeaway is really that we're still reaching."

"We're still interested in the future and the message that we're leaving with this show is a hopeful one, and one that is encouraging the listener to forge ahead," Taylor continued to PEOPLE.

"A well-written song, in our mind, is one that can be reinvented and refined and re-skinned and still be good," he added. "A song like 'MMMBop,' our most known song, we've played it acoustically [and so many other ways] … and now it's wrapped around a symphony and a whole new life and energy comes to it. So our takeaway is that a good song can stand the test of time and can take you to new places."