Stephen and LeAnn Beloyan had struggled for more than a decade to get pregnant. So when they learned they were expecting twins they were ecstatic.
Then, about seven weeks into the pregnancy, they discovered something else. They were not expecting one set, but two sets of identical twins.
"We went from one, to maybe two, but I doubt it, to identical twins, to triplets, to 'I can't believe you're having four babies' within a matter of minutes," Stephen Beloyan told ABC News' "Good Morning America."
On June 7, LeAnn gave birth to Lauren, Sarah, Benjamin and Samuel.
They were born in that order, each one minute apart from the next, by Cesarean section at the Mercer Campus of Capital Health System in Trenton, N.J.
"It was a little frantic in the delivery room," Stephen said. "There was 21 people, doctors and nurses in there."
The Beloyans had undergone fertility treatments and conceived using in-vitro fertilization. That makes twins and other multiple births more likely.
"When we do in-vitro fertilization, what happens is we're placing, one, two sometimes more embryos into the uterus," said reproductive endocrinologist Dr. Seth Derman. "When we place them in, the more we place in, the more likely [they are] to stick."
But the birth of two sets of identical twins at once is extremely rare. Doctors at Capital Health System say it may be as rare as one in 25 million.
The babies were born eight weeks premature, but healthy. Each weighed in at between two and three pounds at birth.
After more than five weeks in the hospital, they are thriving.
Ben and Lauren are a bit bigger than their siblings now, at around five pounds each. They are scheduled to go home with their parents on Saturday.
Sarah and Sammy should be home by the end of the month.
The Beloyans say they're thrilled to go from no children to a family of six.
"Two boys and two girls. What more could you ask for?" said LeAnn. "It's just perfect."
The nursery isn't quite ready yet, but they say they'll make do. And they'll learn quickly how to juggle four newborns.
"We don't know any different," said Stephen.