Gomez played a huge role in the preparations for the wedding, which took place in Dallas, Texas over the weekend, even buying the bride her dream wedding dress.
On the day, the 26-year-old wore a stunning off-the-shoulder black dress, which fell all the way to the floor. She wore a pair of simple black pumps to go with the gown and had her hair in loose waves with a bronzed makeup look.
Gomez was also recorded giving a speech during the reception, in which she tells the bride, "You taught me to be strong." She finished by saying, "I love you," and giving her cousin a hug.
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