On Feb. 24, HBO Documentary Films premiered, “Happy Birthday to a Beautiful Woman: A Portrait of My Mother,”Mickalene Thomas' short, sweet tribute to her late mom.

Based in New York City, Thomas is best known for her elaborate portrait works depicting the beauty and sexuality of African American women. The artist uses rhinestones, acrylic and enamel in her work, and has had showings around the world.

“Happy Birthday” is short and sweet. Perhaps it's too short. At 25 minutes, it introduces viewers to Sandra Bush, Thomas' mom. The film may leave many viewers wanting to know more.

Many years ago, Bush enjoyed a career as a fashion model. Years later, Sandra had a second brush with fame when she became known as “Mama Bush,” the artist's muse for her daughter's work. Thomas is now a respected and acclaimed member of the art world.

When we meet Sandra, she's around 60-years-old, emaciated and dying. Photographs of her skeletal current self are juxtaposed against her runway work from decades earlier: we see the stunning beauty she once was. The older Bush isn't an "aging beauty," she's ravaged by illness but still radiates a spiritual beauty from within her soul. It's heartbreaking to hear her speak of her desire to live, as she notes that her 91-year-old mother is still in relatively good health.

andra speaks of her religious childhood, which was followed by an abusive marriage. While the seeds of feminism were taking root, she had the courage to walk away. As she tells the story of her life's ups and downs, which include battles with addiction, we see more photographs, as well as images of the Thomas artworks she inspired.

The film is a touching portrait of a strong woman facing her end with sadness, redemption and courage. Completely missing from the film is any mention of the fact that Thomas is a lesbian. Viewers who know this might wonder how mother and daughter dealt with Thomas' coming out process. This knowledge, and the works of art that we see in the film, create a yearning to know more about Bush and Thomas' relationship with each other.

As a portrait of Sandra Bush, mother and artist's muse, “Happy Birthday to a Beautiful Woman,” is indeed a lovely film. Had the artist/filmmaker included more of their back-story, it might have been unforgettable.

Sandra Bush passed away in 2012.

“Happy Birthday to a Beautiful Woman: A Portrait of My Mother,” can be seen on HBO on the following dates:

March 8, 11 and 21. HBO 2 will air the film on March 27. It can also be seen on HBO on Demand and www.hbogo.com