By fate.

Gianna was confused. She stared at Arwen, waiting for her to explain. 

And Arwen's smile deepened under her curious gaze as she finally spoke, "You were right when you said I hold my words and promises in high regard, and that I would go to every extent to fulfil them. But Anna, you forgot —I have made promises to your uncle too." 

Gianna blinked for a moment, taking in her words, trying to comprehend if she was hearing exactly what Arwen meant. 

"Of course, I will fulfill my promises," Arwen continued, her tone calm yet resolute. "But I will decide which ones are meant to be kept … and which are meant to be let go. Do you really think I would just walk away?" 

Gianna stared at her, and her eyes sparkled the moment she understood what Arwen was trying to say.