THE PARENTS: Christy Fitzpatrick, 29, and Brian Fitzpatrick, 31, of Upper Dublin

THE KIDS: Graydon Foster and Griffin Maddox, born August 31, 2017

SUBLIME FAMILY MOMENT: Taking walks with the twins in their double stroller and their dog, Denali — named for the mountain in Christy's home state of Alaska — trotting along. "That's our time to catch up," Brian says.

"Baby uno," the doctor said, gliding the ultrasound wand over Christy's belly. Then he paused. "Baby dos."

Please stop counting, Brian remembers thinking. For Christy, the moment brought a wild recap of their back-and-forth journey to parenthood: from being unsure they wanted kids to deciding they definitely did, from a year of wondering whether conception would ever happen to this surreal instant of learning they were having two.

Brian's mind leapt ahead to logistical matters: the room they'd planned as the nursery wasn't large enough for two, so they'd have to tear a different room down to the studs and redo it. "The pressure and realness of the situation hit me," he says.

It was a little over five years since their "meet-aversary," when, at the behest of mutual friends, they showed up for a double date at Xfinity Live. "Do you want to ride the mechanical bull?" Brian asked, and they did—four times.

"I was 23. Brian seemed really fun. That's all either of us was looking for—to have fun," Christy says.

Swiftly, they segued into quasi-living together, with Brian, then based at his mother's home in Cheltenham, spending five nights a week in Christy's Center City apartment. Six months later, they bought a condo, a snug space with no room, regrettably, for Christy's prized pyramid of empty Rockstar energy drink cans, a relic from her college days.

Brian planned to propose in mid-June 2014, but was sidelined by an acute case of salmonella; he spent eight days in the hospital, part of that time rescheduling the caricature artist and photographer who were to be part of his surprise engagement.

He managed to pull off the ruse the day after he was discharged. He lured Christy to Fitler Square, telling her he had a Groupon for a caricature artist (whom he'd already commissioned to create a portrait of the two in wedding clothes).

The artist pretended to make a quick sketch of the pair, then revealed the wedding-outfit picture; meanwhile, Brian dropped to one knee. Christy was speechless.

After their wedding, a November 2015 celebration at the National Museum of American Jewish History, they tiptoed toward parenthood.

"Sometimes we were like: no kids," Christy recalls. "Other times, we thought: one or two. I don't know that we wanted to give up our freedom right away." And once they did start trying, conception took much longer than anticipated.

"It seemed like everyone and their brother was getting pregnant just from looking at each other," Christy says. "And we're both pretty perfectionist, competitive people who go after what we want. It was hard to wrap your brain around."

They sought help from fertility specialists; after one cycle of oral medication, Christy got the phone call: "You're pregnant." She pinned a few paint swatches and some infant T-shirts that said, "I love my daddy" on the walls of the would-be nursery and coaxed Brian upstairs as soon as he came home from work.

"I think I said, 'No way,' and started crying," he remembers.

Despite the gamut of reactions when they told people they were having twins—Brian's buddies teased, "You're screwed," while other people asked, "On purpose?"—and despite Christy's gain of 65 pounds, the pregnancy was "wonderful," she says, with no morning sickness and enough energy to commute by train to her job as a hotel manager in Center City.

They hoped for a natural delivery, but learned at 20 weeks that "Baby A" was breech. The couple scheduled a C-section for Sept. 8. On Aug. 31, Christy's water broke at 3 a.m., followed by a metronome of four-minutes-apart contractions.

She'd made a list for Brian—"Get the dog's food ready for your mom; put my glasses in my hospital bag; take the trash out." But when she emerged from the shower, still leaking amniotic fluid, she found her husband racing around the house in tears.

They arrived at Abington Hospital at 4:30 a.m. By 6, an OB was asking Brian whether the babies had names. The blond one, Baby A, would be Graydon, he said; his dark-haired brother would be Griffin.

Both boys were so tiny and light that when they cried, they flipped themselves onto their bellies, but they didn't yet have the strength to lift up their heads. Christy and Brian, petrified that the twins would smother, took turns staying awake round-the-clock to watch them.

They staggered into their first pediatrician appointment. "We weren't even human," Christy remembers. "She said, 'You guys need to go into survival mode. Put them in a rock-and-play so they can't roll over.'"

Life got easier, then harder. At four months, the twins unlearned how to sleep through the night and began waking every 20 minutes.

Sometimes Christy would bring a baby into the bedroom to tag Brian: Your turn. "Who do you have?" he'd ask, and she'd answer groggily, "I have absolutely no idea." Delirious from lack of sleep, they gave each other pre-dawn pep talks: "We've got to be on the same team."

At six months, they learned both twins needed custom-made medical helmets to correct plagiocephaly, a flattening of the skull caused by being wedged together in the womb. At first, it was hard for Christy to endure the stares from strangers, but she soon honed a shorthand response to their queries: "They have a little flat spot on their heads, and this helps fix it."

The boys are different: Griffin is physically adventurous, but more reserved with strangers, while Graydon readily toddles up to newcomers. As infants, they sucked one another's thumbs and held hands; now they run toward each other with shrieks of delight.

One recent morning, Christy went to wake the twins and found them dozing in identical postures. She whispered for Brian to come look—not just at the boys, but at their bond. "Little butts in the air, heads facing the door. We stood there and watched them sleep."