[She'd known her mother had been upset over the news of her father. Zero had told her that much but Ai hadn't needed to be told. Even all of these years later she saw it in her mother's eyes. No matter how hard she might try to hide it from Ai.
Yet Ai couldn't lie to her mother when the subject of Kaname had come up. It would be impossible to keep it a secret. After all, he hadn't been part of her life in the same way that Yuuki and Zero had been. All Ai had of him was stories and visits to where he lay sleeping possibly forever. Should her mother ever drink her blood - see her memories - she would know that father wasn't present in the way he should have been.
So she'd told the truth. Hurting her mother was the last thing she wanted to do but it would only be worse if Ai tried to hide it.
Time has passed since then but she knows her mother wouldn't want her to see her pain. Which is why Ai gave her mother some space. It isn't really surprising that when she seeks Yuuki out, she finds Zero with her.
For a moment she simply watches from a distance, even knowing that they can both sense her presence. Eventually Ai approaches - the tree between them. Then circles it to take up a spot on the other side of her mother.
She wraps her arms around her mother's waist and leans into her back, inserting herself between the butterfly wings until she can rest her cheek upon Yuuki's shoulder.]