This would have been a great spinoff. And this is how I would see it.

Matt Graduates medical school and the whole family attends his graduation and celebration. After that, a doctor who became good friends with Matt and a sort of Mentor to Matt while at the hospital, helps Matt get his first assignment at another hospital where he transfered to a couple of years before Matt graduated.
Sarah returns as Matt's wife and she is also close to graduation but decided a while back that one OB/GYN in the family was enough and decided to change her major and become a General practitioner.
Ruthie recalls awhile back that Martin had made a statement about him seeing her as a shrink, She also recalls how good it felt when he made that statement and decides she wants to study Pshycology in college and eventually become a pshychiatrist . She also makes a deal with Matt and Sarah that if they let her live with them, she will attend school there. Hence bringing Ruthie back into the sinoff.
Now that Matt is officially a Doctor, he starts to do in the medical word what Eric did in the religious world. Help solve problems. Hence the second episode titled, Mentor.
I already know what this episode is about and it's something horrible that Matt discovers about his Mentor and friend that if he acts on, it may cost Matt his career.