Laravel and VueJS fetching Relationship Data

I have 3 tables and have relationships among them. For example-

• A user has Many Conversations (One to Many Relationship between Users and Conversations table)
• A Conversation has many Messages (One to Many Relationship between Conversations and Messages table)

Now, I want to fetch relationship data via VueJS. For example, I can able to fetch the conversation that is belongs to a user and his ID only from conversation table. Whenever I want to fetch that user data from users table via VueJS, undefined...

Any idea how to solve this issue?