natural to someone—(of behavior, etc.) being in accordance with a person’s habits or character:
- He spoke with a stiff manner that was not natural to him.
natural with someone—
1. = natural to someone:
- This feeling was not natural with him. It was probably only due to some derangement of his own health.
2. behaving in a simple, easy manner towards smb.:
- Mary is caring and compassionate. She was natural with both Kessia and Joshua, and gained their trust instantly.