A/N: First-time Numb3rs fanfic--I got hooked halfway through the season, haven't even seen all the episodes, so please R&R if there are any major oversights.

The front door was unlocked and there was no car in the driveway. Don stood in the foyer for nearly a minute after the screen door had slammed behind him, leaning against the wall and willing away the eyestrain from a day spent in required "enrichment seminars." He played idly with the broken deadbolt, which had been hanging by one screw since he and his father had whacked it moving the hospital bed out of the house after his mother's death. The rental company said their guys would move it, but Alan just could not tolerate having it in the house for one more day. The bolt had been hanging there, half-on, half-off, ever since. Don listened to the sound of the summer evening settling into dusk and ran his fingers over the holes where the missing screws had held everything together. Summer had always been his mother's favorite time of year, and this winding-down hour of late afternoon had been her favorite time of any summer day.

She was worse than either of her sons for counting the days until summer vacation and then frittering them away with half-finished projects and days at the beach. Conversely, Dad was always busiest during the summer, when the long days made for numerous construction projects, each somehow in defiance of its planning ordinance. Alan often wouldn't get home until it was dark. Mom would call a halt to all summer activities around 6 o'clock, though, summoning Don home from Little League or scouts or swim practice and rousting Charlie from his only summer activity, math. The three of them would eat dinner and then move out to the solarium or the back yard with glasses of lemonade, which she made with maraschino cherries and wedges of lime. God, Don had thought that was the most sophisticated thing until he'd gotten to New York and someone…some Manhattanite blind date… had explained it was a Betty Crocker recipe too old to even be considered retro. Amanda was the girl's name, he remembered, and she'd gone on for ten solid minutes about all the artificial coloring and hydrogenated sugars contained in bottled cherries. He hadn't seen much of her after that one date and the lemonade had never tasted quite the same.

He was wondering if his mother had changed the recipe—if there had ever been a recipe, since Mom was inclined to make things up as she went—when he heard a splash from the kitchen.

"Charlie? Hey, buddy…" Don hauled himself off the wall and made his way toward the back of the house, working off his tie, rolling up his sleeves. "You back here? Charlie?"

His younger brother was in the kitchen, but might as well have been on another planet. He was standing at the counter, alternately stirring a pitcher of juice and grading a stack of papers. The papers must be math, because they were getting the lion's share of Charlie's attention. He had a marking pen in his right hand (and another, forgotten, in the back pocket of his cargo shorts and a third tucked behind his ear) and his left arm was extended across the counter so that he could occasionally slosh the contents of the pitcher with a wooden spoon. The sloshing was purely a reflexive spasm because he'd obviously forgotten completely about the kitchen. He looked up once, staring straight at the partial reflection Don cast in the kitchen window, then went right back to his papers.

"Without affect," Don thought, reminded of today's presentation on characteristics of psychopaths. He watched his brother's dark head bent over the notes. He could picture his twelve-year-old self giving a play-by-play account of that day's little league game, his mother drinking lemonade and working her fingers through Charlie's curls as they listened, could see it as clearly as his own reflection in the darkening window. He wasn't really thinking straight, punch-drunk on the half-light and the heat and the sudden silence after a day in conferences and seminars; that was honestly his only reason for what he did next.