Yes, and learning the truth about Christophe.

"It's about our mission, our task to kill Lord Lonato," Byleth explained. "I want to know what actually happened with his son, Christophe. And not your... Official story. I know Catherine was hiding something."

Rhea gazed appraisingly at Byleth for several moments, before closing her eyes and taking a deep breath. "He was involved in a plot to assassinate me. Several members of the Western Church sought to grab power and legitimacy, and Christophe got caught up with them. He was manipulated into believing I needed to die for the good of the Church, but ultimately, he was still complicit, and was executed for his role in the plot."

"...then... Why claim that he was involved in the Tragedy of Duscur?" Sothis questioned. "That makes no sense. Surely, giving over any evidence he was involved in a plot to assassinate you would have sufficed to ensure no one questioned why it was necessary..."

"Because the Kingdom was already unstable after the Tragedy," Rhea replied. "And the Empire and Alliance were growing a bit restless, given the circumstances. We had to stabilize the situation, first and foremost. The Kingdom's ruler had already been killed. If word got out that the Archbishop of the Church of Seiros was also facing potential threats..."

"...it would have led to further fear and unrest. Even the Alliance and Empire would question if their leaders were safe," Byleth nodded. It made sense. Better to use an already known fiasco until things settled. "But why not tell the truth after things settled down?"

"If I did that, that would damage the Church's credibility in the eyes of the people," Rhea shook her head. Sothis face palmed.

"Yeah, but if the truth came out after, then that's worse. If you lie to people out of necessity, but admit it after the point the lie wasn't necessary any more, that would strain the trust the people have, sure, but at least it sends a message that you don't lie to them without good reason, and can be trusted to tell the truth eventually. Keep it hidden though, and you run the risk of trust being outright broken," Sothis shook her head. "And I'm guessing Lonato didn't believe the story anyway?"

"No... He did not," Rhea admitted.

"Great... So not only did you kill that man's son, but he also knows you lied about the reason for it," Sothis sighed. "No wonder he's crashing out..."

"In that regard, I have a request," Byleth decided to move on to the point of this. "I ask on behalf of Ashe, that we attempt to talk Lonato down from his rebellion, and drop the matter if he accepts."

Rhea's face darkened. "Absolutely not. Once one has raised their blade against the Church, against Mother, then mercy is a weakness against such sinners. Call it ruthless, if you wish, but I have learned one thing when it comes to dealing with humans and their betrayals. That ruthlessness is mercy upon ourselves," she asserted.

"Yeah, I'm going to stop you right there. This very situation is a wonderful counterpoint to that," Sothis replied, extending a palm towards Rhea as she spoke.

Rhea blinked. "Mother?" she questioned.

(Cookie for anyone who spots a particular reference in this chapter.)