Okay,

So all my life I have grown up without a dad, and I never really cared a lot until now - I really need money for school though. I have asked my mom in the past who my dad was, and she told me my dad was my brother's dad. (I have two brothers, well we have grown up as brothers, which I guess are my half-brothers. One brother we know has a different father and the other is questionable.) According to my mom the man who I know as my brother's dad, is my dad, and he for some reason doesn't believe me to be his son - according to documents I have found, I was born one month after they were divorced. My mom hasn't always been straight forward with me so I have reason to believe she isn't telling the truth. Back to the point, we don't really look alike and I'm wondering if I could use my DNA and my "brother's" to verify that we have the same dad. We're both over 18, and I could get my mom's DNA (do I need her permission). I realize this would open up a whole bunch of craziness, but I think that if he really is my dad wouldn't he have felt something or wondered every weekend when he picked up my brother?

Thank you for any information