Writer Wendy Clark (well her husband actually) has created a FREE downloadable Story Timeline that will help you keep track.
I think it was last year December that I originally shared this resource on my blog, but now, Mr Wendy has updated it!
Wendy’s Story Timeline is brilliant, and in Version 2 there is a date of birth calculator, so you now have no excuse to ever get confused on what year your character got married (and suddenly realising she couldn’t possibly have married that year because she would have been 12! Lol).
Edited to add: Wendy says “To download, click on file then download on the left. Don’t click red download box as this doesn’t work.”
How do you usually keep track of your story timeline?