My brother is about to get released from prison after 8 yrs?

my brother is about to get released from prison after 8 yrs for aggravated robbery, he is now a Jehovah's witness so he says, (im catholic) any how im scared in a way for his freedom but then again happy and excited, he says he is going to be a better person and he is going to take advantage of life!!! i hope and pray he gets out with a good head on his shoulders and does positive things once he is out here, but for some reason i have a werid felling he is going to be the same person and do bad things!!! i told my husband about this and well he said we are going to have to help him be good he will be living with my sister which is not a very good example she is a good person but very negative, how shall i help?