What are the legitimate rights of the wife's mother and father over the husband, and the rights of the husband's parents over the wife?

The parents of the husband or the wife do not have a special right that obliges the other party to fulfill it. However, good treatment and kindness are required among everyone due to the bond of kinship through marriage (musahara), concerning which the Prophet, peace and blessings be upon him, advised showing kindness to its members. Kindness includes words, actions, wealth, and whatever brings about harmony and affection, along with rectifying deficiencies and faults through good advice and overlooking slip-ups.