For nearly 40 years, everything about Gil Grunbaum's life was a lie, including his name.

He was not, as he had always assumed, the only son of wealthy Holocaust survivors who owned a baby garments factory near Tel Aviv. Grunbaum had been stolen from his mother by doctors at a hospital in northern Israel in 1956, moments after she gave birth.

His biological parents – recent immigrants to Israel from Tunisia – were told their child had died during delivery. They were sent home without a death certificate and denied the chance to see their baby's body or a grave.

Despite his darker looks, it never occurred to Grunbaum that the parents who raised him were not biologically related to him. Now aged 60, he says the discovery was "the most shocking moment imaginable. Everyone I loved – my parents, aunts, uncles and cousins – had been deceiving me for decades."