Sounds natural, just needs a few commas here and there. Let me correct it for you.
My suspicion that my son has an umbilical hernia came true, but doctor reassured that an umbilical hernia would go away by itself as he is growing. To tell you the truth I am a bit squeamish and it is so uneasy for me to see that my son's belly button is like an inflated ball and outside his navel.