A/N: I haven't seen Season 4 yet, so if anything in here gets jossed, I don't want to know about it.
1. She doesn't tell them about the piano. Maybe it's stupid--it's probably stupid, it was twenty years ago and Mer's never said anything about it, not to her. He might have told them himself, in passing, and she might be making a big deal out of nothing, but...
She still remembers music in the house when she was a child. Mer was eight years older, nearly a teenager by the time she was old enough to remember much of anything, but she remembers crawling under the piano bench while her brother played and watching his sneakered feet tapping a little, the way he used to hum along with the music absently when he was concentrating. The way his face would soften a little, crooked mouth untwisting at the corners, how every once in a long while he would flop down on the living room floor afterwards and teach her to build impossible skyscrapers with her blocks.
She was only four when he came home one day and threw out every single music book he owned (and some that belonged to their mother; this led to screaming matches, but Mer has always had a penchant for melodrama). They sold the piano a week later.
She doesn't tell them that Mer can sing, but then, she hasn't heard him in years. Maybe he can't, now.
2. She tells them about the pranks, partly because they're funny stories but mostly because she is so angry at Mer that she doesn't think about what she's doing until afterwards, when it is too late to do anything but be disgusted with herself. What she doesn't tell them is that there was more to it.
Mer was fourteen, and in his last year of high school. Jeannie was six when it happened, and most of what she knows she put together much later; it's another thing Mer won't talk about.
She remembers sitting in the emergency room, kicking her pink sneakers against the chair legs and listening to her parents argue in low voices across the room. They were in the process of a messy divorce and argued all the time, but this was different. Even at six she could hear the undercurrent of fear in their voices.
It was later, maybe a week later, when they finally moved Mer out of intensive care and let her go in with their parents to see him. By then, the bruises had faded to an ugly yellow and some of the swelling had gone down; his face was still mottled and distorted, like a troll's. She remembers the careful way he moved his hands when he talked (one broken wrist, two broken fingers and a dislocated shoulder but he couldn't just stop gesturing, no matter how he tried), the way his blue eyes were dazed and hazy and wouldn't look anyone in the face.
It was the culmination of a year of bullying, and Jeannie still doesn't know what set it off, although she's formulated some guesses since then. It could have just been Mer, with his brilliant mind and his total distain for social interaction; it could have had something to do with Evan, with whom Mer had conducted a brief and intense friendship, followed by an equally intense falling out. He never told anyone who did it, which wasn't really like him, and he started college a few months later in another city.
There is a tiny scar under his left eyebrow--it's not the sort of thing anyone would think to ask about, and the beating didn't leave any other marks. Not on the outside, anyway.
3. She definitely doesn't tell them about the day a few months before that when she wandered into Mer's room to find him sprawled on the bed with Evan sprawled half on top of him and kissing his neck. Mer works for the American military--she's not an idiot. And he was fourteen. Everyone experiments when they're fourteen.
4. She doesn't tell them that she lived with Mer for six months while she was finishing her PhD. Their father had died a few months after her undergraduate studies were over and she'd been living with her boyfriend until everything fell apart. Mer had a big apartment that he was sharing with his cat and his (massive) collection of science-fiction novels, and Jeannie managed to bully and sweet-talk him into letting her move in. She paid the electric bills and cooked occasionally, and Mer used her as a sounding-board for what little research he was doing that wasn't classified. It was the least acrimonious that their relationship had been in years, and she thinks she should have known it wouldn't last long.
She doesn't tell them (or Caleb) about the stricken look on Mer's face when she told him that she was getting married. She doesn't let on to Mer, ever, that she suspected him of being lonely.
5. She doesn't tell them that Rod freaks her out a little bit. Nice as he is—and maybe that's it. There's just something deeply wrong about hearing nice and friendly from a person with Mer's face. She doesn't need to tell them that, though, or that she really does kind of prefer her irritating, irritable, painfully awkward and utterly impossible older brother to this charming stranger. She knows, as Mer doesn't, that they feel the same way.