Seeing a father-in-law and a sister-in-law in a dream indicates that sorrows and problems will end, that he will start to act more comfortably by removing some people who upset him from his life, that he will not neglect his religion and morality under any circumstances and conditions, that he will find relief in every sense, that the problems and troubles experienced will end in a much better way, that he will not leave the truth and the right path, that he will lose what he has earned by putting his life on the line.
Also, seeing a father-in-law and a sister-in-law in a dream indicates that his troubles and problems will continue for a while, that dark and bad days will knock on his door and that this situation will continue like this for a long time, that he will question where he made a mistake, that he will not be able to reach his old success in the work he does and that he will have very difficult times, that he will achieve success because luck is on his side in every matter, that a plan that will bring great profit in a short time will be followed.
Psychologically, seeing father-in-law and sister-in-law in a dream is interpreted as one of the dreamer's family members will pass away, his financial opportunities will increase much more than he expected, he will undertake works that will be a solution for desperate people, he will meet new people and make new decisions, his salary will increase, he will find peace by getting rid of his troubles and sorrows, he will have the opportunity to do what he sets his mind to and he will achieve his expectations from life.