"Andrew Jackson?"
Ethan, who was standing next to Runa and also reading her mother's diary, said the name in disbelief.
"Jackson…," Runa mumbled, then she snapped her fingers and turned to look at Ethan. "Jackson?" Runa repeated her word while pointing her index finger at Ethan.
"My dad," said Ethan. He shook his head as he looked back into the diary. "I can't believe it. My father was your father's friend?"
This piece of the past that was revealed seemed to forge a broken bond somewhere. All this time, Runa felt that there was something between her and Ethan, an inexplicable closeness that made her feel like she had known Ethan longer than she should have. Turns out this is the answer.
Their fathers were friends and now she and Ethan are friends… or at least acquaintances, because Runa can't call Ethan 'friend' yet. There are still many things about him that make Runa unable to trust him.