Any player can make a cadet branch as any house, if you aren't one of the major houses you get a generic named cadet house but if you are a major house then they are named something to do with your house.So i really love the new cadet branch option in the intrigue tab once your Bastard turns 16. I made one while playing the Targaryens 132 years after Aegon's Conquering of Westeros. My firstborn(bastard) was named Raegan and his cadet branch was named Truedrake (white 3 headed dragon with a purple background). He had better stats that my second born son. I feel like this is going to make for a great role play. Has anyone else had a experience like this and if so tell your characters story.
Also Can any major House create a cadet branch? if so i wonder what the starks potential cadet branches are named.
Also if you ever run out of dynasty members and you have a cadet branch you can legitimise them into your house.