I did this. I think what I learned was to never let the truth stand in the way of a good story. But also that truth is often more interesting than anything I could make up. But I was so intent on sticking to the facts that I battled with my conscience mercilessly until I saw that it was useless and ultimately chose whichever route was more effective. Sometimes it was truth and sometimes it was an alternate version of the facts, so to speak. Once or twice, I found out after I'd written the thing that the truth might have worked better. One of my main female characters, I portrayed as a somewhat sexually liberated woman, by the standards of her time and place anyway, and I knew the facts were such that she was to die young, just as she was embarking on adulthood, so I wanted to give her something of a life before I was to take it away from her. I gave her the start of an exciting career at a law firm and a budding romance, and I think it works because by the time she gets sick and is sidelined from her life, she already has a lot to lose and the downfall is thus a more drastic plunge. But after I'd written the book, edited, done and done, I learned that she'd been pursuing a life as a nun when she became ill (Lupus, I believe) and was ejected from the program when they found out she was sick and therefore had no future worth investing in. (excuse the clumsy terminology--I am not a good Catholic) But I think there's a possibility that may have been a more interesting story thread to pursue. I did hear back from an elderly great aunt who liked everything about the book except for what I had done to her sister.