['One time I had a flat tire and my dad came to help me fix it.', 'Oh no! Glad your dad was able to help. How did it happen?', 'I ran over a nail in the road.  Now I know not to drive near new houses.']
That's some bad luck. I hope it wasn't too much of a hassle.
A situation when I felt grateful was when I had a flat tire and my father came to help me with it.  I felt grateful to have family around to be there for me.