Any way to find out who owns a private account?

This is a long shot I’m sure but my wife is being harassed / bullied by a private account. No idea who this person is or why but they obviously know my wife ad they’ve mentioned our children by name in multiple messages. I know she could just block and move on but this person is sending threatening messages and obviously knows personal details about us. Is there any way to get a name for who’s behind the account?