The Hanson baby boom continues!

Taylor, the middle brother of the rock trio Hanson, and his wife Natalie are expecting their fourth child this winter, they tell PEOPLE exclusively.

“Each of our kids has made life richer and more exciting,” gushed Taylor, 25, and Natalie, 26. “We can’t wait for this guy to join the party.”

Their little one will join six cousins, including two recent additions: Zac and Kate Hanson welcomed their first child, Shepherd, in May and Isaac and Nikki Hanson welcomed their second baby, Monroe, in July. (Isaac’s son Everett and Taylor’s previous kids – Ezra, Penelope and River – round out the bunch.)

This fall, the brothers will have their hands full as they set out on their recently-extended Walk Around the World Tour – with babies in tow. As Zac recently told PEOPLE: “We may have to think about getting a second bus!”-people