Assalam alaikum,
The only thing that I don't understand is that Allah sayas he will only punish us for our sins he will not punish us for the sins of others. So why would the two grandchild be made blind because of the sins of the gran parents? Insha Allah somebody can answer as I can't see that this could be true. Would Allah punish two innocent people for the sins of thier relatives?
Fi amanillah,
Sumaya