They do. Especially if the initial story becomes a series. The significant events/lessons learned that occur in the story are added to the sheet.

Any changes to the character help to make the characters more complex and interesting. Like in real life people change as they experience life, so should our characters.

Don't worry about your characters changing. There are no "perfect" characters. When they become multidimensional and believable, then readers fall in love with them and the readers continue to read the story to find out what happens next. The readers are invested in them.

Phoenix