"Daddy, when can we go to the library?" Ella asked in a voice that was flirting with whine status.

"Honey, we just went two days ago."

"We already finished those books, Daddy," Adah says, as if it was idiotic to even consider otherwise. "We need more."

Don leaned back on the couch, only one of his sneakers untied. At the moment, it was difficult to consider going out again, having just come back from a run that had left his entire shirt soaked with sweat. Really, it was hard to consider anything but a freezing cold shower.

"Maybe once I've showered, girls."

"Maybe?"

It was times like these where Don cursed the fact that his daughter's had not only inherited some exaggerated version of his wife's love of reading, but also her permanent attitude. He pauses, considering his words carefully. Should definitely, or anything remotely in that category, pass his lips, he would be forced to go to the library, under threat of hours of loud and petulant protest from his kids.

"I will really try my best to make time to take you two to the library today, okay?"

At this, they seem satisfied, and go back to drawing.

Much to Don's surprise, neither Ella nor Adah had much of any interest in TV. Whenever he watched it, they climbed into his lap and whined about being bored and wanting to do something else. They had never once asked to watch it, only inquired as to what on Earth made it so appealing to their parents. This was a blessing and a curse. On one hand, he never struggled with the problems Danny unendingly complained about related to the form of entertainment – fights over whose turn it is to pick what to watch, the desire to spend hours in front of mind-numbing shows, worries that too much television would melt the kids' brains. On the other, there was no constant activity to fall back on. The world of two seven-year-olds was ripe with want of a simple source of amusement for the plethora of times that Mommy and Daddy were busy – cooking, showering, on the phone, washing clothes, cleaning up.

Of course, both girls could sit, with an ample supply of books, and read for hours without speaking once. The problem was that "an ample supply of books" meant just about an endless reserve. And for parenthood standards as high as Jamie's (healthy, home cooked meals every night, a spotless house that minimized things on which to choke, bruise, or trip) mixed with a desire to shower and wear clean clothes every day, sometimes Don felt the only solution was to move into the city library.

At that moment, Jamie appeared, hair wet from a recent shower. "Girls, come on. I'll take you to the library while Daddy showers, how about that?"

Eager squeals from the twins follow, and a feeling of relief washes over Don. He was now but minutes away from no longer being covered in sweat.

The girls do not have to wait to be told to get ready. They race around, finding socks and shoes and the library books from their last visit. Don watches them from his perch on the ratty couch, in awe, as usual, as to what God blessed him with such perfect children.

Identically perfect, he always said. Because the girls were, in nearly every way, completely identical. No one, excluding himself and his wife, could tell them apart. Both had short bodies, thin in the extreme, despite the food they shoveled back at every meal. Both had unimaginably cute faces framed by the thickest, curliest of brown hair, which they insisted on keeping long – so long, now, they nearly sat on it. They liked and disliked the same foods, books, activities. They both existed in a constant state of motion, from the long list of sports they played in the span of a week, to the squirming every time they were forced to sit, to the way they fiddled with their hair as they read. They were, to say the least, a handful, but they were the kind of handful that you could not help but enjoy nurturing and lifting up, feeling as though, in the process of helping them, you were touched by some sort of magic.

They were equally matched at everything. If they read two books of similar lengths, they finished at the exact same time. If they started with the same amount of food, they declared themselves full in unison, leaving the exact same quantity and types of foods on their plates. What one found sad, the other found sad. What one found funny, the other found funny. They were ticklish in all the same places, enjoyed wearing the same types of clothes. They were best friends.

The pair now stood by the door, shoes tied, books in hand, waiting for their mother to strap on her sandals. Don smiled at their identical expressions of impatience, which erupted into uncontained annoyance when his wife could not find the car keys.

"We can walk, Mommy," Ella said.

"Sweetie, it's twelve blocks from here," Jamie replied as she lifted up the loaf of bread on the counter. "Now I had them when I came back from the drugstore…"

Realizing the keys were on the critical path to more books, the girls both, in the same instant, mobilized into a two-person search party, leaving – literally – no stone unturned in the apartment. It took about three more minutes of tearing the place apart to find the guilty keys, which had somehow managed to fall behind the dresser in the bedroom.

Once the sounds of his family had died down, the door closed and the three girls in the elevator, Don took a deep breath. He felt as he always felt when they left, slightly relieved, slightly tired, and very empty. Sometimes it was a good empty, as it was now, with the knowledge that he might be able to manage a thirty minute shower without interruption. Other times, like when he left for work, it seemed as if the emptiness has created a vacuum inside of him that would continue to grow until he got back to his daughters.

Some infinites are bigger than other infinities, as Riemann said. And some handfuls are more filling than other handfuls.