In this only reported incidence of Addison's disease in half-siblings, the adrenal failure is postulated to be a sex-linked recessive character. Adrenocortical antibodies were not detected.
Bickham, Richard E.; Silvestre, Dora; and Mellinger, Raymond C.
"Addison's Disease in Half-Siblings,"
Henry Ford Hospital Medical Journal
: Vol. 16
Available at: https://scholarlycommons.henryford.com/hfhmedjournal/vol16/iss2/8