A father-in-law who wishes to help you and your family may at times seem like he is controlling and inconsiderate, like the time he gave your daughter cookies for dinner. However, setting boundaries and being assertive, while at the same time being gracious, is an effective way to deal with a controlling father-in-law, especially in front of your children. Telling him what you want and being respectful at the same time are important in letting him know that he must respect your choices and encouraging him to follow your wishes, especially regarding your children.
Acknowledge respectfully to your father-in-law, with your spouse, if possible, that you appreciate his thoughts and help when he keeps buying your children toys you don't want them to have or insists on staying for two weeks when your newborn arrives. This is important to help him feel validated and respected. A father naturally wants to help his child and grandchildren by providing wisdom and material goods. Recognize that your father-in-law probably has the best of intentions.
Assert your decision-making to your father-in-law calmly. This does not mean being rude and disrespectful. Tell him that you appreciate his thoughts and opinions, but that you and your spouse have made a decision. Use a patient and respectful tone of voice, especially in front of your children. Avoid intentionally insulting your father-in-law, as he is still the grandfather of your children, and you should serve as a model of respect and try not to influence your children's feelings about him.
Listen to your father-in-law’s side. Actively listening means repeating back the information that you hear him say. This acknowledges how he feels. Avoid statements like “You always…” or “You never…” Instead, try, “I hear you saying that…,” and put aside thoughts of interrupting him. Then, tell him specifically what you want him to do. You might say, for instance, “I want you to be involved in our lives, but I would appreciate it if you would respect our choices.”