Upon receiving all the information, Kain fell into deep thought.
In his mind, he was piecing together the sequence of events, starting with Mera's mother.
Back in the Foggy Dungeon, Mera had revealed her past to Kain. From that, Kain deduced that her mother was likely being pursued for some reason. She had left her family, leading to the current situation.
And then, whatever it was that caused her to be pursued had been inherited by Mera, her daughter.