Pet cat is squinting in one eye

Question
I have an 18 month old cat that was originally a rescue animal.  Very sweet and my only companion.  For the last few days I've noted that she seems to be squinting periodically from her left eye.  Nothing in it that I can see.  No obvious redness or swelling.  When I gently try to wipe her eye with a moist towel, she tolerates it OK and it doesn't seem to be hurting her.  No other changes in her behavior of any kind and she seems otherwise as frisky as ever; no change in her eating!  Can you help me with her?  Is there anything I can do to help or do I need a vet?  Thanks.

Answer
There are many things that can cause this squinting, and you might not be able to see what it is as it could be very tiny.

She could have an eyelash stuck into a tear duct. She could have a hair under her third eyelid. She could have piece of rug or weed from outside under her eyelid.

Your best bet anytime an eye is involved is to have it looked at by a vet. Better to be sure than sorry!