Why was the name 'Marvel Family' changed to 'Shazam Family' in DC Comics?

The name 'Marvel Family' was changed to 'Shazam Family' primarily due to legal issues and trademark conflicts with Marvel Comics. When DC Comics acquired the characters from Fawcett Comics, Marvel Comics already existed and held trademarks on 'Marvel'. To avoid confusion and legal challenges, DC Comics eventually rebranded Captain Marvel as Shazam and consequently renamed his associated heroic group the Shazam Family, especially in the modern era and adaptions.