According to your weight I’m not surprised that your granddaughter’s finger got stuck inside your belly button. There were probably some injuries on the skin in or around your belly button. According to your weight I suppose that you have massive fat tissue at the anterior abdomen that creates wet conditions ideal for developing skin infections. You can visit your GP to examine your belly button. If there is an infection present (omphalitis) perhaps some local antibiotics and antiseptics can be prescribed.