Presidents and First Ladies Trivia

[wpbinzel]

Many thanks to Bill Binzel for submitting this trivia question:

What was the name of the physician who is believed to have assisted in the birth of Mary Ann Todd, the future Mrs. Lincoln, and beyond the delivery of his wife, how was the physician associated with President Lincoln?

Roger got the answer to the first part of the question, and Eva found the answer to the second part. I am not going to post them for a couple of days in the event that others want to attempt to find them as well.