I don't own Firefly or its related characters, Joss Whedon does.
Some days River felt normal, or as normal as a genius reader with massive assassin skills can feel. Other days she felt Everything, saw Everything, heard Everything. It hurt.
It got better after Simon came for her. Normal became a little more common, as impossible as that seemed to those watching her. And Everything became a little less. After Miranda, she wasn't hearing Everything trying to get out as well as Everything trying to get in anymore. It hurt less.
It hurt even less because it was a familiar Everything. Out in the black she knew what to expect.
There was Captain Daddy with his hidden guilt and lost faith, who snapped and snarled and loved everyone.
There was Zoe's permeating grief and strong loyalty, and sometimes, slowly strengthening, that streak of laughter.
Under Zoe's grief, River could hear the echo of Wash still rattling around the ship. She always promised to watch his dinosaurs for him.
Inara was a study of contradictions, regal and pretty and poised, but hurt and scared and rebuilding her view of the 'verse since Miranda.
Jayne stalked and stormed and acted angry and stupid but secretly grinned over his home even when Captain Daddy was ripping him a new one.
Kaylee was all bubbles and joy, especially since she and Simon came together. River tried not to listen in some nights. It wasn't fair.
Simon was strong these days, had found hope in love even as he feared the loss of everything for his sister's sake.
But under it all, she could hear Serenity singing to the black, echoing Kaylee's bubbles and Captain Daddy's faith. Serenity understood grief and joy and shared it all with River. When the voices got to be too much, she would go to the cockpit and focus on Serenity's song, letting it carry her through the stars.