"Liam's feeling good," she said. "He has to, you know, rest up, but he loves this film. He's so proud of it and I really wanted to be able to represent it for him."
"He just needs to take care of himself and getting healthy is more important than anything," she added.
On Monday, Hemsworth Instagrammed a picture of his Isn't It Romantic co-star, Rebel Wilson, posing with Cyrus, as well as solo shots of his wife at the premiere. The Australian actor said he was dealing with health issues and also thanked Cyrus for the support.
"Sorry I couldn’t make it to the @isntitromantic premier tonight guys," he wrote. "Been dealing with some pretty annoying health stuff the last couple days. Lucky I have the best girl in the world to represent for me! Thanks for the support babe! I hope everyone enjoys the movie! It’s a perfect Valentine’s Day flick so if ya ain’t got nothin better to do then go see it! Love to all!"