With a big brood, it's "the more, the merrier," says the "outnumbered" musician
Credit: Bryan Johnson

While four kids may sound like a handful to many, for Taylor Hanson, the arrival of his newest child, son Viggo Moriah, didn’t send his stress level over the top.

“After two kids, you’re outnumbered,” he tells PEOPLE’s Celebrity Baby Blog with a laugh. “So once you cross having three, having four is not such a big deal.”

Viggo’s digging the big family, too. “He’s so interested in what everyone is doing around him,” says Hanson. “He loves to be in the middle of the action and doesn’t want to miss a thing.”

There’s no shortage of action for Hanson, 26, wife Natalie, 25, and their brood (left to right: Penelope, 4, Viggo, 7 months, River, 2 ½, and Ezra, 6 ½).

“I think it’s pretty much ‘the more the merrier’ for them at this point,” says the proud dad.

For more with Taylor (and a larger photo!) visit PEOPLE’s Celebrity Baby Blog.