The Father, the Son, and the Holy Spirit are one. God exists, outside of what we can consciously comprehend. Jesus, lived and died for our sins. Jesus existed, and now exists with the Father, again, outside of what we can comprehend. They do not "exisist" in our eyes, because we are blind, until we can truly see.
My prayers go out to the family and friends of the family who are in anguish, cancer hurts the ones the love the affected to. My prayers also go to his mother. Always good to be specific in prayer. Also, my heart goes out to all affected by this very unfortunate situation.