If so, what did you do? A. Nothing and it has not spread. B. Nothing and it spread - Now I need a new windshield! C. Had it repaired D. Other I believe this will be interesting to you in seeing how people's priorities differ.
I lived with a chipped windshield for five years or so, then asked some one to fix it (insurance company pays it) So, I thought I would get it fixed.. The guy came and was WOW you had it for five years? If I try to fix it, it may crack? Ok, then just leave it as it is, it was OK for 5 years and I just need couple of more years and I will sell the vehicle. He convinced that he would try to fix it and stop if he see the windshield cracking.. Sure it did and he stopped and left .. it is well over a month.. It staying strong.. I will keep it that way until I sell.. (hopefully in the next couple years)
It is better to replace the entire windshield once you notice the defect (provided you can afford!) rather than waiting for it to spread and start withering away...
I have to answer "all of the above" to this one. I have had just about every situation happen to me with windshields.