Or how about someone who became a vegetable because of severe brain damage being restored to their original intelligence? How about someone who lost a liver or their kidneys and had those organs miraculously grow back?
What about the opposite cases where parents relied on faith healing to save their children, and their children died?
The only answer that makes sense for all these cases is that god doesn't heal, and medical science doesn't currently have every answer.
Because our definition of healing is different from God's definition. He heals us by taking us sinners who live in a corruptable body and cleansing us with his blood, hence allowing us to enter the kingdom of Heaven. There are times when he chooses to heal the sick, or when he chooses spiritual healing. A good example is in the book of Luke where they placed a paralyzed man before Jesus, and he forgave his sins:
Luke 5:17-26
17 One day Jesus was teaching, and Pharisees and teachers of the law were sitting there. They had come from every village of Galilee and from Judea and Jerusalem. And the power of the Lord was with Jesus to heal the sick.
18 Some men came carrying a paralyzed man on a mat and tried to take him into the house to lay him before Jesus.
19 When they could not find a way to do this because of the crowd, they went up on the roof and lowered him on his mat through the tiles into the middle of the crowd, right in front of Jesus.
20 When Jesus saw their faith, he said, "Friend, your sins are forgiven."
21 The Pharisees and the teachers of the law began thinking to themselves, "Who is this fellow who speaks blasphemy? Who can forgive sins but God alone?"
22 Jesus knew what they were thinking and asked, "Why are you thinking these things in your hearts?
23 Which is easier: to say, 'Your sins are forgiven,' or to say, 'Get up and walk'?
24 But I want you to know that the Son of Man has authority on earth to forgive sins." So he said to the paralyzed man, "I tell you, get up, take your mat and go home."
25 Immediately he stood up in front of them, took what he had been lying on and went home praising God.
26 Everyone was amazed and gave praise to God. They were filled with awe and said, "We have seen remarkable things today."
It is better for any of us to have our sins forgiven then to receive physical healing. Even someone who is a vegetable, is a lifetime in this life being a vegetable so bad if the end result is eternity in Heaven, where you will be given a new body, a perfect body? Sometimes we don't see the big picture like God does. He knows all, even knows what is going to happen in the future. What if the reason a person was a vegetable was because God knew that person was going to follow the wrong path if he did not intervene? Maybe my cousin who was taken at an early age was on his way to destruction, and God had to swipe him up before it was too late?