Shawn Mendes has got Camila Cabello's back.

The musician showed his support of the former (!!!) Fifth Harmony singer and his "I Know What You Did Last Summer" collaborator on Twitter on Tuesday (December 20), quoting Cabello's latest Twitter post about her departure from the group and writing, "'Pursue what makes your heart pound, happiness is our responsibility' beautifully said."

And his timing couldn't have been better: His response came just hours after Fifth Harmony clapped back at Cabello with a scathing message on Twitter, where Lauren, Dinah, Normani and Ally accused the "Bad Things" singer of skipping out on group counseling sessions and other efforts to mediate the music group.

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