The Voice of Hind Rajab, a harrowing account of a Palestinian child’s death in Gaza, won the runner-up Silver Lion

US indie director Jim Jarmusch unexpectedly won the coveted Golden Lion at the Venice film festival on Saturday with Father Mother Sister Brother, a three-part meditation on the uneasy tie between parents and their adult children.

Although his gentle comedy received largely positive reviews, it had not been a favourite for the top prize, with many critics instead tipping the Voice of Hind Rajab, a harrowing true-life account of the killing of a five-year-old Palestinian girl during the Gaza war. In the end, the film directed by Tunisia’s Kaouther Ben Hania took the runner-up Silver Lion.

Divided into chapters set in New Jersey, Dublin and Paris, Father Mother Sister Brother features an ensemble cast including Tom Waits, Adam Driver, Mayim Bialik, Charlotte Rampling, Cate Blanchett, Vicky Krieps, Indya Moore and Luka Sabbat. In a four star review, the Guardian’s chief film critic Peter Bradshaw described it as “a film to savour”.

“All of us here who make films, we’re not motivated by competition. But this is something I truly appreciate, this unexpected honour,” said Jarmusch, who made his name in the 1980s with offbeat, low-budget works such as Stranger Than Paradise and Down by Law.