Sponser My Family

[QNA]

Hello,
I tried reading through various websites but haven't been able to locate an answer, hopefully some one can help me here.

I am a US citizen for 6 months now and want to sponsor my family. I have 2 brothers, one is 23 yrs old, other is 16 yrs old. My parents had also adopted a child who is 12 yrs old now.

1- Do I have to put in a I-134for everyone? I know I have to put in a separate one for my 23 yrs old brother, but do i have to put in a separate for my 16 yrs old brother and both my parents?

2- Do I sponsor my adoptive brother also or he is automatically sponsored with my parents?

3- Is the fee for every form submitted or does one fee cover my whole family?

Your help is greatly appreciated.