Chiquitito's Last Hope: Your Help Needed

This is Chiquitito. He is 13 years old and he's very sick. I have taken him to different doctors and they haven't been able to find the problem. He has problems urinating and now also walking. The doctor is recommending an MRI, but unfortunately, I have already topped off all my credit cards and went through my savings. I need help to be able to pay for this test. This is my last resource. Any help I can get to save my baby's life will be helpful.