The title characters of Lieven Debrauwer's brief and leisurely paced but ultimately rewarding Belgian domestic drama, "Pauline & Paulette," are two single sisters in their 60s who live apart from one other in a small town between Brussels and the sea.

Pauline (Dora van der Groen) is severely mentally handicapped, with the sensibility of a small child, and is cared for by a third sister, Martha (Julienne De Bruyn), who allows her to spend her days watering the flowers and running undemanding errands.

Pauline also idolizes Paulette (Ann Petersen), a portly woman who runs a fabric store, surrounds herself in shocking pink and is the diva of the local operetta company -- a 30-year avocation that is her true passion and "reason for living."

The self-absorbed Paulette finds the fawning Pauline an embarrassing nuisance and has basically shut her out of her life. But when Martha suddenly dies and there's no longer anyone to give Pauline the 24-hour care she needs, Paulette has a big problem on her hands.

So the movie has the helpless and not always lovable Pauline shuffling between the exasperated Paulette and a younger fourth sister, Ceclie (Rosemarie Bergmans), who is kinder and well-meaning but, in her own way, as incapable as Paulette.

At first, the subject matter of this smallish movie may seem both off-putting and cinematically overly familiar. But it gradually comes together to be a poignant and gently humorous parable that loves its characters and communicates something rather beautiful about human nature.

With a steady eye and a warm (but never overtly sentimental) heart, it explores a territory where few movies have ventured before: the often painful relationship of siblings late in life, and the strain that the passing years can place on it.

The two sisters are so completely natural that I assumed they must be gifted non-professionals. But as it turns out, van der Groen and Petersen are actually two of Belgium's most accomplished actresses who just happen to be giving the performances of their careers.