Cuz,

Sandy had a root for Frederick Douglass that could keep him safe from a notorious slave driver. And the story the followed turned Douglass's mind from bondsman to free man.

Sources and Further Reading

PBS:

https://www.pbs.org/wgbh/aia/part4/4p1539.html

Narrative of the Life of Frederick Douglass, an American Slave : https://docsouth.unc.edu/neh/douglass/douglass.html

Libarary of congress

https://www.loc.gov/collections/frederick-douglass-papers/articles-and-essays/