Hello, Welcome to Healthcare Magic. I have read your question fully and understand your concerns. The lump in the back of the neck could be a lymph node swelling. When there is an infection in the body, the lymph nodes nearest to the source of infection swell up. Lymph nodes are important parts of the body’s immune system, and they help to fight against any infection. Your child is having cold, which is an infection of the upper airways/ears. So, the lymph nodes in the head and neck area would swell up. The lump in the back of her neck would be an occipital lymph node swelling. Once her cold infection settles down, the lymph node swelling would settle down too. Sometimes, the swelling remains as long as 6 weeks. If the swelling persists beyond this time period kindly see a doctor. You should also see a doctor sooner if this swelling enlarges, becomes red or painful or if the child becomes more ill than before. In children cold like symptoms are very common. They easily catch the infections from their classmates/friends at school, these infections are mainly viral, and they settle down within 2-3 weeks. These infections help to build your child’s immunity. Your child needs supportive treatment during this time like steam inhalation (if she can do it), saline nasal drops, oral fluids, paracetamol etc. You can also keep her room slightly humid. Regarding her becoming “fatty”, I am assuming you mean she is gaining weight. Children of growing age need to eat healthy well balanced meals. So cut down on intake of high fatty/high calorie/high sugary items. Encourage her to take up a sport/dancing/gymnastics etc. I hope this answer has helped you. Thank you Regards Dr Sunita Sayammagaru