I had a dream as if my father-in-law had passed away.
Dreams of death can be quite scary and unnerving, but they do not necessarily predict actual death or doom.
Dreams about the death of a family member can represent a deep fear of loss and separation. Since your father-in-law is your spouse's father, it may be that you have concerns about family relationships and the future of your marriage. Alternatively, the dream could be a reflection of your own feelings about death and mortality.
In any case, it's essential to keep in mind that dreams don't always have a straightforward interpretation, as they can take on different meanings depending on your personal experiences and emotions. If you're feeling particularly worried or anxious about the dream, it might be helpful to discuss it with your spouse or a trusted friend.