This man's cat came to the defense of his son when attacked by the neighborhood dog. (WARNING: Video contains graphic content at the end).
Video credit: Roger Triantafilo (YouTube)
Video Description: My cat defends my son during a vicious dog attack and runs the dog off before he can do additional damage. Thankfully, my son is fine!
Video link: https://www.youtube.com/watch?v=C-Opm9b2WDk