This is very strange - Along with my 3 rotties, I have a mixed shepherd - she is about 4 years old now. When I adopted her from the shelter 3.6 years ago, she had the typical shepherd colorings i.e. black from her nose up to around her eyes... after a year that black area all turned grey

- I wasn't sure as to why - especially as she is a young dog... However I have began to notice this 2 weeks - (2 years after it started turning grey) the grey is now turning back black again

- I am not sure what this means? has anyone experienced that - is there any explanation?
..Its great to see her back to her original color being restored, but why did her black hair go grey in the first place and why is it now changing back after all this time? - I thought she was going to be grey now for ever