We have a cat, Gato who went away five days ago and returned two days ago (which is a very long time for a cat as they return at least once per day when they get food).
After returning back he just slept the whole day, didn't eat and all in all looked very "depressed". We thought he just needed some sleep as he was walking very long. But he didn't stop and he didn't sleep anyway. He is just sitting there next to the water, looking into it and doing nothing. Yesterday he almost fell into the water, he can't walk on straight lines sometimes and he doesn't eat.
He doesn't look sick, his eyes are normal, his fur is a little bit messy (probably from his adventure) but he doesn't look good either.
So what could be wrong with him and how can I help him?
I already asked my parents to take him to the vet but they don't want to and say that everything's ok with him. What should I do?
which is a very long time for a cat as they return at least once per day when they get food
While common, that is not a given. There are cats who sometimes go on longer excursions. It depends on how able they are to hunt, how much there is to hunt, and the weather.