She's a household name who's sold tens of millions of albums, performed in front of dozens of sold-out arenas and remains one of pop culture's foremost trendsetters.

But Miley Cyrus couldn't have looked more like a superstar than she did Thursday, visiting fans from room-to-room at Rady Children's Hospital in San Diego, California with her fiance Liam Hemsworth.

The Grammy-nominated singer surprised patients at the Southern California medical facility as she popped in to pose for pictures and share encouraging words in an unannounced visit.

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Happiness: Miley Cyrus, 24, and beau Liam Hemsworth, 26, surprised fans at a San Diego children's hospital Thursday, posing for photos and spreading joy

Gratitude: Miley on her Instagram page thanked the facility, Rady Children's Hospital, for their 'incredible dedication to bettering the lives and health of the beautiful youngins'

Happy: The pop star and actor beamed as they moved from room-to-room greeting fans

The hospital said on Facebook, 'Today we received a surprise special visit from a couple of people you might recognize!

'Thank you to Miley Cyrus, Liam Hemsworth and The Happy Hippie Foundation for bringing joy and laughter to our patients!'

The 24-year-old Tennessee native dressed in her usual array of bold, loud colors, clad in a shamrock green skirt with yellow, brown and purple flowers, a pink coat, mauve leggings and pink rain boots. The Wrecking Ball artist had her hair pulled back with a yellow bow and a few pink barrettes holding things together.

Good cheer: Miley was a ball of energy as she surprised patients at the facility for kids

The We Can't Stop singer's hunky beau Hemsworth, 26, wore a blue plaid shirt with dark blue jeans, with his brown beard perfectly trimmed on the visit.

On Facebook, plaudits poured in for the pop star amid her well-intended stop at the medical facility.

'Thank you Miley for stopping by [Rady's] today for our kids,' one user wrote, adding, 'It's people like you that puts [big] smiles on the [kids'] faces and what a sweet memory for them.'

Super girl: Miley lit up the faces of the young patients at the hospital with her infectious smile

Another person added, 'Now this is a side of Miley I'd love to see more of! Makes way more of an impact than her crazy antics.'

The Happy Hippie Foundation is Miley's charity organization earmarked toward rallying 'young people to fight injustice facing homeless youth, LGBTQ youth and other vulnerable populations.'

Miley and Liam's stop in San Diego is presumably one of the last in the states before they depart for his native Australia, according to the Herald Sun, which reported that the celebrity couple are headed down under in the 'next few days' to ring in 2017.

Thankful: 2016 was a strong year for the starry couple, who rekindled their longtime love

Her cause: Miley's appearance was on behalf of her Happy Hippie Foundation, which she started to address causes she holds dear

'They will have New Year's Eve in Australia again this year,' a source told the newspaper, adding that their itinerary likely includes a stop at a music and arts showcase called the Falls Festival; and in Byron Bay, an oceanside town in New South Wales that the two are partial to.