Despite Thor's complaint, Frigga kept her smile on, confident. But she made a sigh, once she and Thor were alone, outside the room. "She's the link between you and your brother! I [i]created[/i] her; that's why she's not one of us", she began to explain quietly, almost desperately for her eldest son to understand. "Haven't you ever wondered about Loki's true feelings? The feelings he has never told anyone? Your brother's been sitting in the dark of that cell, reveling in his own anger, and trapped in his mind and body! Believe me, my son, I tried talking to him. But there was nothing he wanted to say", the queen sounded sad at the recollection of watching Loki sit in a corner of that box. 

"When you and Loki were asleep, I took a fragment from each of you. Those two fragments make up Ava's own mind; she can see your memories, your desires, your burdens. Even your personalities and gifts, making her half of you, and half of him", she was softly explaining this to him. "See her like a mirror; she reflects you and him. If you ask her anything about him, she will reveal what you have yet to see. She'll do the same for him", she then placed a gentle hand on his cheek. "Live your lives. She will help you both. When your brother's not around, ask her. Or just generally talk to her", she finished softly.