I sympathize with you a great deal, not too long ago my situation was very much like yours. I, however, am the youngest in my family and the only who has thus far woken up. After I realized that my entire life and its "spiritual" goals had been built on lies and delusions I had many conversations with my parents over several months. It was like talking to a brick wall, nothing I said sunk in, no evidence I provided swayed them, they were incapable of conceding a single point in my favor even if they could not answer my arguments.
So, I started leading something of a double-life. I reached out to old acquaintances from college to build true friendships with and met new people as well. I started spending quality time getting to know them while my parents thought I was at the gym or studying. I realized very quickly that it was a situation I could not endure for long because it was tearing me apart. So I started working on finding a place to live and figuring out a budget, saving up money, etc. Until finally about a month ago I had everything I needed to approach my parents and tell them I no longer wished to attend the meetings or try to get reinstated, I had been DF'd about a year earlier, unfortunately I was much like your brother, so eager to get baptized at the young age of 10 years old. (A decision that I was once proud of, but now see as perhaps one of my greatest mistakes.)
They were stunned, to say the least, we talked for a long time. I told them how I was miserable at the meetings and knew that I could not get reinstated feeling this way. They told me that they weren't going to kick me out, but apparently, they spoke later and changed their minds on that. If I wasn't going to the meetings they didn't want me there.
So, I followed my carefully laid plans to where I sit right now. At my desk, in my new room, in a house that I share with true friends. Friends that would never cast me aside because I didn't share their beliefs. It was hard getting here, and it's hard work staying here. I've got three part-time jobs right now and summer classes. My free time is limited, but I'm figuring out to make things work. I miss my family, I miss the people still inside that I once called friends before I realized how tenuous those relationships were, but I don't miss the religion one bit, I don't miss their God, and I'm pretty sure that's because he was never anywhere but my own imagination.
It's not all freedom and good times away from the Organization. Sometimes I do feel sad for what I have lost, but overall, I would say I'm happier now. Finally, for the first time in my life, I don't feel confined by the mental and emotional prison constructed by the Watchtower. Finally, I feel as if I am free to seek my own path instead of following the one I've been forced to walk since birth.
I can't tell you what to do, it's your life, and your choice, but hopefully my story will help you decide.