Selah as Child?

I want to make a sort of major change, and that is in Selah's character. I don't want to put the event (Child) a long time ago, lost in antiquity. I want Selah to be the Child, the one who ended Peterny's civil war.
Pros:
It was ten years ago.
Cons:
It was ten years ago. It's still clearly in the public memory, and it makes it Cor's problem. It might have happened around the same time as Garlanda's death. Matthard, though he claims innocence of age, is less a participant than Selah. But, I kind of like that what they did as children affects where they are now.

Here's how it would read, in dialogue form, from Selah to Matthard:

"We were living in Plock when it was invaded, ten years ago. I was ten, eleven when we moved to a camp outside the capital. A place for new 'Peternians' the king didn't want running down to Landria for help. We were to the north of the city, so we would have to go through it to run south. We also met the Northerners preparing to seige the city. You do know about the famine, I hope?"
"The most embarrassing, selfish part of the story? Yes, I think I've got that down."
"They told us about everything. Informally took over the camp, since most of the guards were won over by their stories. After four days of watching them prepare for a futile, bloody battle, I left. Walked twenty miles to the capital city. When I got there, they must have thought me a Northerner, given all the cooing and feeding. Later, they told the Notherners I had moved their pity. The war was stopped and negotiations began."
"And Landria had some mysterious interest in that?"
"The war kept Peterny busy. Britaca didn't mind it either. There were even special factions within Peterny that were outraged at the war's ending so soon. They sent mercenaries after political officials, the king, and us. We fled south after six months. Landria is safe. It used to be said that the king was the only one happy to see us."
"But that was ten years ago. You've had a change of-- oh. Right."
"Now, we stay 'Peternian' to keep paranoia alive and the border closed."

So....
I think it adds to Selah's character.