All those years ago, during the rebellion, was the death of Elia Martell and her Targaryen offspring. Whilst Robert didn't necessarily order their deaths, the children were two less Targaryens to deal with. Even if they were babes.
But as Robert sat there on his knees, he felt regret, because now he was paying the price for letting it happen. Before him laid his younger sister, the girl was convulsing and panicking as blood spilled from her, and Robert couldn't do anything to help her, other than hold onto her and curse the Gods.
"Hold on, girl."
Robert grunted, trying to act strong despite the pain building in his chest at the thought of losing his younger sister, sweet and innocent. She had only been a girl during the rebellion, she had always been an innocent. And yet... so was Elia Martell and her children. An innocent for innocents.
"Hurry up, you blubbering fools!"
Robert barked, his voice thundering through the halls of the Red Keep, fury mixing in with his pain. The maesters were being painfully slow, the longer they took, the closer to death his sister got. Robert glanced back down at her as she heard her sputter his name.