[quote=Erklings25]
Seriously. I do want one but why do they exist and do you get invited onto one or what. I do want to join one so please tell me how it works.
[/quote]

If you're aiming for a 'roleplay family' in the sense of a following or common group, I'd definitely just develop a back-and-forth with other players. You like how someone writes? Tell them that, let them know you hope y'all can continue to work together, and just have some conversation. If you have similar interests you'll probably meet up again, or can intentionally choose to follow one another to games you find particularly impressive. These groups can grow really beautifully. As someone who GMs now an then, having that 'family' is a nice promise of some support when you open something new. That said, it also can be intimidating or downright unwelcoming to new players. 

I want to emphasize what I just said there. Personally, I feel very unwelcome some roleplays because of these 'roleplay families'. While they can be amazing for players in the fold, one disagreement can spread like ink in water. Opinions can bloat more than they ever would normally, and without direct interaction, you can find yourself generally disliked and treated roughly by people you never even knew existed. So, if you find one of these families or help make one, please remember to treat others kindly.