Just to Rant: MIL gave my daughter mcd even when i say no.

I am so fed up and wanted to rant. Im a ftwm and I usually reached home at arnd 7pm. My husband is selfemployed. Ive 2 kids (eldest 4yo) and most of the childcare during the time when the kids came home (armd 6pm) to when i reached home is taken by my helper and husband. Today my husband has an appointment at night. When my mil knew of this (at arnd 4.30pm), she suggested that she n my fil came over to my hse to help my helper take care of the kids. Sometimes they do that, so i agreed, especially since my husband niece n nephews r with my pil tdy. After I agreed, my mil informed that she would be buying mcd for the niece n nephew AND my eldest for dinner. I immediately called her and told her not to buy my eldest portion as my helper had already started cooking our dinner. She said ok. However, when I came home, I saw my eldest eating mcd. When I told my eldest to eat the dinner prepared by my helper first (my eldest is ok to eat the dinner prepared at home and readily accepts), my mil told my eldest not to worry and to eat mcd first. When she done eating mcd, she is too full to have the dinner prepared at home (of course!). My mil jist ask us to pour away the home cooked food my helper had scooped for my eldest. Im so upset with this. Firstly, my mil ignored and overwrite my instructions. Secondly, its not like my eldest dont want to eat home cooked food. How can she ask her to eat mcd (not so healthy food) before a proper meal? Thirdly, she disregard that there will be wasted food cooked by us. I understamd that she wants the kids to be happy. I would not mind mcd for dinner if dinner had not been prepared yet. I am also ok if my mil had let my eldest finish home cooked food before eating mcd. But fact is, the dinner had had been cooked and prepared, i even called to inform her and specifically ask her not to let my eldest eat mcd, she agreed only to overwrite my instructions later, and even asked my eldest to eat mcd first and throwing away the home cooked food where so much effort is taken to prepare and wasting it. Im so so so angry and upset. #ranting #MotherInLaw