Liam Hemsworth missed the Grammy Awards because he was in hospital.

Liam Hemsworth

Liam Hemsworth

The 29-year-old actor was not at Los Angeles' Staples Center on Sunday (10.02.19) to watch his wife Miley Cyrus perform with Shawn Mendes and again as part of a tribute to her godmother Dolly Parton because he had fallen ill and had been receiving treatment elsewhere.

Liam's 'Isn't It Romantic' co-star Rebel Wilson explained the actor was missing from group interviews and his other commitments due to an unspecified medical problem.

She told 'Extra': "Yes, he texted us this morning -- he was in (the) hospital overnight, so hopefully he will be fine."

Instead, Miley was joined at the ceremony by her younger sister, Noah Cyrus.

She shared a photo of them together on her Instagram account and wrote: "My #1. The coolest girl I know. Sickest songwriter. Vocalist . Style Goddess. & above all the best little sister I could've ever asked for. [heart emoji] @noahcyrus @recordingacademy (sic)"

She also posed on the red carpet with her parents, Billy Ray and Tish Cyrus and took to her Instagram story to share a throwback photo of herself as a child attending the Grammys with her country superstar father.

A spokesperson for Warner Brothers confirmed to People magazine that Liam had woken up feeling unwell so pulled out of his press commitments to promote 'Isn't It Romantic' on Sunday to recover.

It is not clear what is wrong with the 'Hunger Games' star or whether he will be fit to attend the film's premiere with Miley on Monday (11.02.19) as they had originally planned.