RALEIGH — With triplets on the way, Kevin and Kristine Sullivan expected a jumbo-sized bundle of joy – a chubby-cheeked, diaper-clad threesome.

But the heavyweight trio that bounced into their lives last October drew gasps of surprise even from doctors at WakeMed: 18 pounds, 11.48 ounces total – the size of a Christmas turkey.

It turns out the Sullivan clan wasn’t just big, but Guinness World Records big. It’s official as of July 7: No other set of triplets on Earth can match their precious poundage.

“We’re up to 24 bottles a day,” said their dad, a research scientist. “Between feeding and changing them, you have about a 45-minute downtime.”

If the Sullivan babies seem small for a Guinness mention, consider that the average triplet weighs about 4 pounds. Quintuplets come out even lighter.

Days before their birth at 35 weeks, doctors told the Sullivans to expect typical trips.

Then came Kate: 6 pounds.

Ethan: 7 pounds.

Owen: 5 more pounds

“A couple of them were as big as full-term babies,” said Dr. Joel Bernstein, their ob/gyn with Raleigh’s Kamm McKenzie practice.

The Guinness idea started as a wild stab – checking the Guinness site for the reigning champs. The Sullivans beat a set of Canadian triplets by a pound, though paperwork and verification took months, including video footage of a nurse calling out each triplet’s weight.

The Sullivans aren’t the all-time heaviest. That honor goes Mary McDermott’s three born in England a century ago. World records are often broken into categories, and the Sullivans of Raleigh are recorded as heaviest living triplets.

Just as surprising as the triplets’ size, they spent no time in neonatal intensive care and went home from WakeMed after three days. They ate with no problem and slept ... well, like most infants.

After nine months, Kate is sitting up, Ethan is scooting and Owen has grown into the biggest sibling at 24 pounds.

Their parents, also juggling their 3-year-old son Wyatt, can’t guess why their multiples turned out so titanic. They aren’t unusually large people themselves.

If the record stands, they figure their children will regard it as a curiosity, a unique trait they can use as an ice-breaker in conversations when they get older. And after they’ve wowed people with their world-record status, they can wait for the satisfying response: “My, how you’ve slimmed down.”

Shaffer: 919-829-4818