The problem of casting when a character must age throughout a story is a clear problem: do you use one actor, with a lot of make-up, or cast different people in the same roles? The need to make family members resemble each other is also a problem. In Ivan Svazbo's film, 'Sunshine', a most imaginative solution of these difficulties were found, with Joseph Fiennes playing members of three generations, each at a certain period in their lives, with others playing the same characters at different ages. In 'Sixth Happiness', the adult narrator plays the himself as a child. This is not a Potter-esquire construct (although there's some knowingness here), but more a response to the character's condition (shared necessarily by the actor): brittle bone disease, which restricts one's ability to grow. In fact, the actor (Firdaus Kanga) is also the author of this semi-autobiographical story, adding another twist.
The story looks at the problems of living with this condition, the stress it puts on the character's family and also on the way that the expectations of others can be as disabling as any physical defect. It also looks at the strange world of India's Parsee community (also featured in some of the novels of Salman Rushdie), and provides a glance at the many faces of modern Bombay. And yet although it is a film of some distinctiveness and humour, I didn't actually enjoy it very much. In some ways, it never quite escapes the feel of validation: in every scene, both the outcome and the purpose of its inclusion in the story seem clearly telegraphed; and while the character pleads to be treated as a normal man, his disability and the reactions it induces are at the centre of every scene. The affected portrait of the Parsees is also somewhat cloying, a sympathetic tumble with a straw man that tells us little about how India is today.
Ultimately, the use Kanga as narrator, which makes the film self-aware of its breach of the usual conventions of casting, is probably the biggest mistake: with each episode interpreted for us, I felt (rather like I did after reading Philip Roth's 'I married a Communist') that I had spent a little too long in the company of a man with a little too much certainty of his own correctness. Thus the tale (and its conclusions) seem forced upon the audience. It's a shame: the tone mars some interesting content.