That villager can reappear. However, because the game does have a genetic-type working, you will need to find the right parentage to beget that type of villager. There are events which can alter appearances as well, but they cannot be predicted.
_________________________
Why is it that if someone tells you that there are 1 billion stars in the universe you will believe them,
but if they tell you a wall has wet paint you will have to touch it to be sure?