Thursday April 4, 2013 AT 9:00 PM on CBC-TV
Saturday April 6 at 11 pm ET/PT on CBC News Network
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In nature, sibling rivalry can be murderous: one in four spotted hyena pups is killed by a litter-mate, while the black eagle's progeny is even more ruthless. The first chick to hatch makes sure its brother or sister never makes it out of the nest alive. That struggle for supremacy extends to humankind, too: the book of Genesis describes how Cain killed Abel in a fit of jealousy because God preferred his younger brother's offering to his own.
Viewers who don't get along with their own siblings may be relieved to see they're not alone. Montreal filmmaker John Curtin presents us with some famous siblings - professional hockey's four Staal brothers, business tycoons Harrison & Wallace McCain, writers Christopher & Peter Hitchens, Hollywood superstars Olivia de Havilland & Joan Fontaine - whose supercharged childhood rivalries have extended well into adult life.
As Curtin, a Gemini Award-winning filmmaker reveals, blood may be thicker than water, but it can also be a lot messier. While partners and friends can come and go, siblings, for better or worse, last a lifetime. Entangled from infancy in a web of conflicting emotions, few people escape unscathed from their brothers and sisters. That rivalry, as old as Cain and Abel, is sometimes just as nasty. Our siblings know us more intimately than anybody we are likely to meet in life. And they know exactly how to hurt us. What are the root causes of these often troubled relationships and how do they make us who we are?
Many of us have brothers or sisters. And many of us are, or will be, parents. We know that sibling relationships are often fraught with tension, competition for the parents' attention and affection and, sometimes, damage that can last a lifetime. In SIBLING RIVALRY: Near, Dear & Dangerous, John Curtin has made an absorbing film most of us can relate to - whether as children or as parents.