Amelia Anisovych was filmed singing the Frozen classic in the bunker as Russia attacked Ukraine, and the video has been seen by millions.
After fleeing her home country with her siblings and grandmother to Poland, she appeared at the Atlas Arena in Lodz to perform the national anthem in front of thousands.
Amelia singing in the bomb shelter
The concert, “Together with Ukraine”, was created to help support those suffering following the Russian invasion.
Many of Ukraine and Poland's biggest name entertainers took part in the show in aid of Polish Humanitarian Action.
Amelia previously thanked people that "enjoyed my singing" on BBC Breakfast.
She said: “I practise singing every day in the morning, afternoon and evening... it has always been my dream to sing.”