Imagine you’ve reached the fine age of 77 and you hear news of a school reunion. You’re going to have the chance to meet up with several of your former classmates who you haven’t seen since you were fourteen-years-old. They’ll look a lot different, of course, but what about their personality? Will they be broadly the same as they were back then?
Past research that’s looked at trait changes from adolescence to mid-life has shown there tends to be a moderate amount of stability, so too research that’s looked at changes from mid-life into old age. Put these two sets of data together and you might expect to see at least some personality stability across an entire lifespan. Your classmates probably won’t have changed completely.