rasknr, OP is not the Sponsor of his father in law to take him as dependent. @OP, If your father in law's profession is not eligible for on arrival visa don't take the risk of taking him with you without arranging a visa for him as they are very strict in on arrival visas. Either you check with someone in Dubai to arrange the visa for your in law or check with the Embassy if you can get it.
rasknr, OP is not the Sponsor of his father in law to take him as dependent. @OP, If your father in law's profession is not eligible for on arrival visa don't take the risk of taking him with you without arranging a visa for him as they are very strict in on arrival visas. Either you check with someone in Dubai to arrange the visa for your in law or check with the Embassy if you can get it.