Love Story by Erich Segal (season 3)c
After failing (i.e., after Jenny fails to conceive), they consult a medical specialist, who after repeated tests, informs Oliver that Jenny is ill and will soon die. Oliver then tries again. While this is not stated explicitly, Jenny appears to be suffering from leukemia.
....As instructed by his doctor, Oliver attempts to live a “normal life” without telling Jenny of her condition