Dominic Sherwood is proud of Sarah Hyland.

The Shadowhunters star opened up to ET's Leanne Aguilera at Comic-Con 2017 in San Diego, California, on Thursday about his Modern Family star girlfriend's recent response to being criticized online for being too skinny.

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"[I'm] incredibly proud," the 27-year-old actor gushed. "As the public knows, Sarah's going through quite a bit at the moment. For anyone to be small-minded enough to try and close her into a space that they don't understand is ridiculous."

"The way she deals with it is incredible," Sherwood added.

Meanwhile, Hyland and Sherwood are going from just being a couple to co-stars, as the 26-year-old actress is joining the Freeform show's cast. Sherwood shared that having his gal around at work was great.

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"Everyone fell in love with her on set," he said. "It was a real joy ... she's been coming in since season one, coming to visit me. Having her on set as an actress was just phenomenal."

"What's nice about it is when we get to set, it wasn't so much boyfriend-girlfriend, it was two actors," he added.

Sounds amazing!

Watch below for a sneak peek at Hyland on the show.

And check out our Facebook Live interview with the cast below.

Sherwood's co-star, Katherine McNamara, recently dished to ET about Hyland's appearance on the show.

Watch the video below for more.

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