Cat defends Young Fox being attached by Fox

(sorry video goes out of focus) There is usually only 1 fox and sometimes another..but on this nite looks like mother Fox brought along younger Fox..big mistake as it was attached by Male Fox and bitten...our fearless Cat "Hairy" jumped in and tried to Stop the abuse..the fox run off & younger Fox retreated to nearby fence..we checked later and could not see anything...but unfortunately young fox was found next day curled up as if asleep (dead) with deep bite mark on stomach...poor little fella