Could brothers or close kin join the same contuburnium?

[Jason Micallef]

Hello everyone this is my first post on these message boards. I have a great interest in Roman history and am actually writing a novel about a soldier and his journey in the legion. 


I am very stressful when it comes to historical accuracy and i really want even the littlest deatails accurate.

So what if close friends or two brothers decide to join the legion at the same time? Will they be sent to different legions or could they be kept together in the same contubernium or at least the same legion?
Also to add further could a younger family member join into the same legion or contubernium as his older brother if he requests so?

I appreciate any help 
Thanks