I don't think Sam's character is written off for good. In life, he had a predisposition to see ghosts of past (his sister). Perhaps its a genetic family trait we'll see more of.

She came back to him after discovering she was pregnant. She now wants her baby to grow up with a father, especially her own father. Women are particularly in higher need during pregnancy, too. She'll probably divorce the Butz again later. NOW THATS REAL WORLD!