With the birthday girl's glittering ballgown ... Princess Isabella of Denmark's 18th bash was one to remember. Denmark's royal family and it-girls arrived at the lavish Royal Theatre's Old ...

with the Danish royal family releasing three different photos to celebrate the occasion. As is tradition, she received her first tiara as an 18th birthday gift, and the stunning turquoise piece ...

The royal teen dressed up for a family outing to see a performance at the Royal Theatre's Old Stage in Copenhagen in honor of her milestone birthday DA MARIE ODGAARD/Ritzau Scanpix/AFP/Getty ...