Please enjoy lovely niece, singing "At Last".
16 year old Rain Ward of Austin, Texas performed At Last in a contest and won second prize.
"At Last" is a 1941 song written by Mack Gordon and Harry Warren for the musical film "Orchestra Wives". It was performed in the film and on a record by Glenn Miller according to Wikipedia. It looks like there is some discrepancy about what other movies it was in and who performed them when I look at Youtube. Miller seems to have made several recordings.
Personally, I find the most moving rendition by the incomparable Etta James in 1961 Recently, it was recorded also by Celine Dion and Beyonce, both of whom, in my opinion, I think do not do the song justice the way my niece does.