Making her dad proud. Vanessa Hudgens absolutely dominated the Rydell High hallways during Grease: Live on Sunday, January 31 — despite losing her father the night before.

As previously reported, Hudgens' father, Greg Hudgens, passed away from stage IV cancer on Saturday. She announced the news via Twitter and told her fans that she would do the show in his honor.

“It was incredibly hard for her," a source tells Us Weekly, "but she’s a true entertainer, so it was on with the show."

Audiences praised Hudgens, 27, for her "There Are Worse Things I Could Do" solo and her strong performance following such a family tragedy. Her longtime boyfriend, actor Austin Butler, was also in her corner through it all. He even visited her on set during rehearsals for the pep rally scene. As Hudgens’ bad girl character Rizzo chatted with Aaron Tveit's hunky Danny Zuko, Butler blended in as a student just a few feet away.

"He would come by a ton of Grease rehearsals to see how she was doing or just to be supportive and sweet. He also went to the taping yesterday," a second source tells Us of The Shannara Chronicles actor. "He couldn’t not be there for her. He is so proud of her and thinks she’s so strong."

Butler, 24, knows what it's like to lose a parent to cancer. His mom, Lori Butler, passed away of the disease in September 2014. He tweeted about his loss at the time and called Lori his "hero" and "best friend."

"He was by [Vanessa's] side nonstop and having been through the same situation with his mom, he was very understanding," the source adds.

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