That's Gunhild Carling. After seeing that, I had to watch more videos of her, and I found out that her whole family is that talented. The Carling family is from Sweden and they've been performing since the early 1980s. I can't believe the amount of talent they have. They play multiple instruments, sing, and dance. According to their web site, her mother plays banjo, violin, drums, and double bass; her father plays trumpet; her brother Max plays violin and clarinet; her sister Gerd plays piano, harp, organ, trombone, alto sax, and vibraphone; her brother Ulf plays drums; and Gunhild plays...well, watch the video montage below:
I also really enjoyed the following clip from a concert her jazz band did (and the video and audio quality is excellent). She fronts the band, playing trumpet and trombone, singing, and directing. It's a little long (3 songs), but worth it. There are guest dancers for the first song, she wrote the second song (which I love), and her father wrote the third song. Several Carling family members are in this clip (mother on banjo, father on trumpet, brother Max on clarinet (and I think sax), and brother Ulf on drums).