Demi Lovato paid a surprise visit to patients at the Children's Hospital Los Angeles on Thursday (30.03.17).

Demi Lovato

Demi Lovato

The 24-year-old singer shocked the children at the referral centre in Los Angeles, California, which deals with young kids who are battling a critical condition that needs life-saving care and attention, yesterday to show her support of their Make March matter campaign, according to ET Online.

The brunette beauty brought an extra smile to the children's faces when they were given an advanced screening of her in the upcoming movie 'Smurfs: The Lost Village', in which she provides the voice over to Smurfette in the animated production, and were visited by a person dressed as her character.

But they were taken aback even more when the 'Cool For The Summer' hitmaker walked through the doors straight after the blue figure strolled in.

The Children's Hospital has taken to social media to share a string of pictures of the 'Camp Rock' star during her trip, which include a photograph of her posing with the Smurfette and a patient, as well as other images of her with the children being treated at the centre.

They captioned the Instagram post: "Smurfette ventured out of her village to find out she wasn't alone--She found the kids at CHLA! She also brought along the #SmurfsMovie and the voice of her character, @ddlovato. Thanks for helping us #MakeMarchMatter! (sic)."

And Demi is not the only star who has decided to surprise the young adults at the hospital, as 47-year-old actor Jack Black and 'Keeping Up With the Kardashians' star Kim Kardashian West, 36, have previously visited the centre earlier this month.