Beautiful But Broke (1944)
It seems that there was only one Brian Sisters film released in 1944: Beautiful But Broke, in which the girls sang a really super song, I'm Just Another Blues, that was a complete performance within the film (a 'low budget' movie, which was released on 28th January, so just scrapes into 1944 - but it must have been filmed during 1943).
This is a really swinging song, not like the earlier, 'little girl' performances. The girls were allowed (encouraged?) to use their own arrangement, and it works very well indeed. So well that it was filmed in a single 'take'.
The Brian Sisters had really grown up!
The singing is very good - obviously not dumbed down by the film's director! You can watch this performance again and again. The Brian Sisters are clearly enjoying it too.
Watch out for:
There are a few moments in this performance when Gwen looks rather as if she would start laughing – but she managed not to. She was always inclined to be rather boisterous and to clown around.
Doris and Betty remain somewhat more serious, but cast occasional cautious glances at Gwen!
The YouTube offering below only includes the soundtrack from the movie.
Beautiful But Broke is sometimes available on DVD; get it if you have the chance.