Achilles My Pit Bull

I need funding to get my Dog Achilles the pit bull neuter being he has become very agressive with my other household pets Maximillion my cat, and Taylor my other dog.  I do not wish to give him away being he apart of my family in which I inherited from my daughter while she went off to College.  Achilles have a great home and plenty of food from a mother who loves him beside his brothers.  Please help with medical bills which can become quite expensive due his sizes and height he is big boy of 90 lbs.  Yes I am trying to work on that diet of his (smile)  thanks in advance for your assistance and support.