Her title of "Doctor" (of Humane Letters) is an "honorary degree" given largely to those who have shown 'humanitarian' and 'development professionalism'. All her 'doctorates' were received while she was the wife of VP Biden.
There is no academic studies or knowledge needed, and the most common way to receive this "degree" is through large sum donations, or social/political favor. She did not attend any the five colleges that granted her "Doctorates".
Her working resume at this time included waitress, model, substitute teacher, mother, wife x2 and Lady VP.
Her academic resume includes Brandywine Junior College in PA for one-semester and BA in the English Language, which she has spoken since birth, from the University of Delaware that she used to be employed as a substitute teacher for less than 1 year.
She does have a Ph.D. which does entitle her with the honorific. Most people only use it in the realm of academia, however. We all know it stands for Piled Higher and Deeper. Medical doctors also earn Ph.D.'s but also the M.D. and are actual Doctors. Regardless, she is cringe as fuck.
She has an Ed.D, not Ph.D. While spoken Dr. Biden, in writing per the AP Style Manual/Guide, it would be Jill Biden, Ed.D.
They reserve Dr. XYZ in print for medical doctors.
Same difference. It's still a doctorate. Again, it's cringe to use it in public but whatever.