as difficult as it is to live with atopic dermatitis, watching a loved one live with it, while trying to find treatment that works for them must be even more difficult. Glad you have found this community, and hopefully you will find support and resources to help you get through this.
If they haven't already been seen by a dermatologist, I would strongly recommend seeing one. (I presume the cortisone was prescribed by a family doctor not a Dermatologist) There are many treatment options available nowadays, aside from cortisone. Have possibly allergies been discussed? One thing that I have recently found helpful between my appointments, any questions I may come up, I jot down on my phone notepad, and when I have the appointment I have all the info in one place.
While we can't offer any medical advice here, living with AD for closer to 40 years now, I can share from lived experience.
Often the products that are coming in contact with the skin, can add more irritation. Taking a look at the shampoo, body wash to something that is more skin/allergy sensitive may help. Also, not to be overlooked is the laundry detergent. Even as an adult now I am extremely sensitive to, is the laundry detergent I used. I only use Ivory Snow. Look out for products that have the seal of approval can be a great start.
https://nationaleczema.org/eczema-products/?pg=1&ppg=6
Also, there's a great article written by Emma you may find helpful
https://atopicdermatitis.net/living/managing-new-triggers-is-a-balancing-act
Lastly, as difficult as it is, patience is a key component in getting through this. For some people it can take a lot of trial and error to figure out what causes flares, what will work and what won't work.
Please do let us know how they are doing, and if you have any questions.
Sending love and healing prayers to you and your great grandchild!
Chava (Atopicdermatitis.net) Moderator and Contributor