I think the father really loved his daughter in the previous timeline, he has a weird way of showing it (or not showing it) I think bc he doesn’t want anyone to know his weakness or sum, maybe. I think he took her to the safest jail so no one would harm her while he figured shot out to help his baby girl. He probably gave her a knife to protect herself in case and told her to wait for him but his wording was an issue and I think that’s why she misunderstood. The prince went there not to harm her but to help, probably, but in her panic she killed herself. That’s why he tried to stop her once he knew what she was about to do. That’s my thoughts, I haven’t read no spoilers so I could be 100% wrong lol