I will say in advance that Susan was somewhat of a difficult character to write for! I tried to do her justice, but no promises!
Leaning casually against a tree, polishing his sword absentmindedly, Edmund spotted his older sister, Susan, taking aim at a target with her bow. He watched as her brow furrowed, and then as she released the string, sending the arrow into the target, dead center. He had heard what Father Christmas had told her. "Trust in this bow and it will not easily miss."
And apparently she did trust in it, because every time, she was a perfect shot. Susan shot a couple more arrows into the target, and then turned away. She began walking towards the How, but then noticed Edmund and stopped.
He arched an eyebrow as she strode over to him. Susan was changing, it was clear. She was acting more like an adult, even more than Peter. The things she said mirrored her logicality and stubbornness. Though she was a difficult person to understand, Edmund felt like he was finally getting to know her, at least parts of her.
"What are you doing here?" she asked when she reached him.
"Standing and observing," Edmund responded dryly. "What about you?" Now he was enjoying himself, poking a bit of fun at his sister.
Susan frowned at him. "Preparing for battle. You should be doing the same."
Edmund rested his hand on the pommel of his sword. "No worries there, Su."
Susan looked like she would like to add something more to her earlier statement, but instead, stood silently and glowered at the field full of warriors.
"I hate this," she said suddenly.
Edmund cocked his head in question.
"We're sending all of these people into battle."
"We will be fighting alongside them," he answered softly.
"I know. But it's going to be awful. Look at them! Remember last time when we were here? So many Narnians, and they were all willing to fight, and they were strong and conditioned. But now…there's barely any left. The Telmarine army is enormous. How many will die?" Susan finished in a whisper.
Edmund knew how much his sister hated warfare. She was Queen Susan the Gentle, after all. He sighed. "It's going to be…well, not good. But these people need to fight."
"I know. How many will be left though? Will it be worth it in the end?"
"I don't know."
Susan and Edmund stood in companionable silence for a time, each wrapped up in their own thoughts. Edmund remembered back to the day when he had been brought back to the Narnian army. He and his siblings were sitting and eating, ravenously, in his case.
Peter finished telling his three younger siblings that he wanted them to return home, and then looked at them in a sorrowful way.
"But they need us!" Lucy cried. "All four of us!"
"Lucy, you almost drowned. Edmund was almost killed!" Peter exclaimed, the torment clear on his face.
Edmund watched his youngest sister and agreed with her. "Which is why we have to stay." Looking around at all of his siblings, he continued, "I've seen what the White Witch can do. And we can't leave these people behind to suffer for it."
Susan had been observing Peter, Edmund, and Lucy for a time. "I guess that's it then," she said, rising to her feet.
"Where are you going?"
"To get in some practice."
Out of the four Pevensies, Susan had readily acknowledged that the battle was going to happen. Though she might despise fighting, she had been the adult, taking charge and making sure everyone else knew what they were doing.
"They'll be okay, Su. Whatever happens. They know what they're getting themselves into."
Susan nodded. "I know. But it doesn't make it any easier."
"No, it doesn't."
A few more moments passed before Susan said, "I'm going to find Lucy. I'll see you later, Ed." She smiled and began walking across the field.
Edmund gazed after her, eventually tilting his head against the tree and closing his eyes. Susan was the responsible one. If anyone could keep them together in this troubled time, it was her.