Laravel simple private conversation

I am trying to create a simple private conversation between two users. I've tried following some examples but all i can find is for multiple users in multiple conversations and more complex versions. My endgoal is for simply be able to do $user->conversations->messages to get all my conversations and their messages that has been sent between two users.

I currently have 3 models for this.

User Model
Conversation Model
PrivateMessages Model

My tables currently look like this but i think i need to do some changes to them also.

users:
id
name

conversations:
id

private_messages:
id
sent_by
sent_to
body
read_at
conversation_id

via Chebli Mohamed