Dad must tell her these three sentences.

Mature rationality

First sentence

Baby, if someone likes you, it means you are excellent. Dad is glad that dad will always stand behind you.

You can talk to dad about anything.

The second sentence

You have someone you like, and your father is happy for you, which means you are beginning to grow up. Dad also believes that you will encourage each other to become better.

Third sentence

When you learn to protect yourself, you learn to do things. Dad is not against your falling in love, but afraid that you will get hurt. You just have to keep your bottom line safe, your father supports you, and your experience of feelings.