Your daughter is having Down syndrome.
There is an extra chromosome. It is also called trisomy 21
There is delay in mental and physical developments.
There is a risk of development of many medical conditions.
Respiratory diseases,eye diseases,thyroid diseases,obesity,intestinal abnormalities,siezure, childhood leukaemia
And most important is a susceptibility of development of infections.
Your daughter may be having irritant or allergic dermatitis
on neck.and it may spread to genital area and followed by secondary bacterial infection.
You do not worry, simple measures may improve her condition.
Antibiotics with steroids
in tappering dose will improve.
Local antibiotics oint. may be applied on infected areas.
Antiseptics like dettol may be used for bathing.
Immunobusters,vitamins and nutritious food should be given for the prevention of infections.
I hope your daughter might be benefitted.
However,you should remain in touch with consultant either dermatologist
Dr. Ilyas Patel MD