Really feel for you, so very young. Thank goodness she has you both, who are knowledgeable.
One of my twins developed spots that gp confirmed were guttate all over her back, she is 16, but they have gone in a period of 6 weeks and her derm appointment has only just came up.
My 12 yr old is still fighting the flakes on her scalp, tried the alternative thread in that it was doogro oil but it irritates her scalp, now will have to get gp appointment for derm appointment even though I know that it is psoriasis.
Yes, feelings of guilt are normal, as a parent we are powerless to stop these things from happening, but by being there and supporting them through we will always do what we can for them. Please dont feel bad on yourself this was not your fault.
Sharon.