Your daughter weighs 7.1 kgs at 9 months of age. This falls around the 10 th percentile according to the WHO growth charts. But this one value of weight at this age has no meaning. What was her birth weight
and weight gain pattern after that? Has she stopped gaining weight adequately after starting on solids?
If she is gaining weight adequately in accordance with her birth weight then you need not worry. But if that is not the case I will need to know the diet you are giving her and if she has any other problems besides milia. You should give her home made food , it should be soft but not watery. Increasing the water content decreases the nutritional value of the food. You can add extra oil/butter and sugar in her food to increase the caloric intake. Give fruits rather than fruit juices. Gradually introduce all common food items in her diet. Your aim should be that she should eat almost everything that you eat by the time she is 1 year old. Ensure that you are making the formula exactly as per the instructions. If you can share with me her current diet and food items commonly used in your house, I can help you formulate a diet plan
You mentioned that her milia resolves on its own and then recurs. Milia in infancy usually resolves on its own by the time the child is an year old. It is not something you should worry about. If you are really bothered about it you can mail me her picture when you feel that it has increased. ( My mail id is firstname.lastname@example.org). After seeing that I will be able to help you better.
Hope this helps. I can guide you better if you can reply to my queries.
Wishing you good luck.