We recommend bringing a friend who is also studying the same subject of course!
Aside from that, you're welcome to bring anyone. For younger students, this might be a playdate or a family friend. For high shoolers, this could be your best mate or even partner.
Ultimately, make sure you invite someone you get along well with and who both have similar goals and want to learn!
Your tutor will involve both of you in the learning process and make lessons as interactive as possible.