Brothers car has had a windshield chip for over a year now, probably closer to a year and half. Says it hasn't grown any, so if it's existed this long then is it something to worry about still or should it be fine?
probably nothing to worry about but....
The integrity of the windshield is compromised. The chip in the nice smooth surface creates a point of failure. The chip is the weakest link in the chain, so to speak.
Under these circumstances you could lean against the windshield and the force could start 'that crack' which spreads across it in short order.
A lower cost solution to replacing the windshield could be a chip repair. Most windshield retailers have the additional service of placing a vacuum on the chip to suck the air out of the crack and then use a glue or resin to fill the crack. As the vacuum is removed and the chip area is pulling atmosphere into the crack it, instead, pulls in the resin, filling the tiny cracks and adding integrity to the windshield surface.
Here are some DIY chip repair kits. You would want to select one with a hand vacuum tool or pump.
As well, you could have a service do the work for additional cost.
Not sure about other countries, but in the US, windshield replacements are covered by insurance at no cost, and with no increase to your insurance rates. (Note: I have comprehensive coverage, so this may not be true for liability coverage.)
I though otherwise, until a month after buying my new (used) car, I had two windshields replaced in a two week span, as I happened to get a chip on the freeway that perpetrated into a crack due to the high temperature fluctuations we were experiencing at the time. I asked my agent if my rates would go up and he was happy to dispel the urban myth that windshield replacements will spike your insurance rates.