Greyfriars Bobby was a Skye Terrier who became known in 19th-century Edinburgh for spending 14 years guarding the grave of his owner until he died himself on 14 January 1872.
Rockstar North reference this in Grand Theft Auto V, and later Red Dead redemption 2.
https://www.edinburghlive.co.uk/news/edinburgh-news/greyfriars-bobby-red-dead-redemption-15470996