F amily reunions in European arthouse cinema are almost always unhappy events, on a scale of strife that ranges from simmering resentment (Louis Malle’s Milou in May) to spectacular score-settling (Thomas Vinterberg’s Festen). There are still splatters of bad blood on the Sunday best in the films of Carla Simón, but the Spanish director has a rare gift: she makes you leave the cinema with renewed faith that having relatives and keeping in touch with them may actually be a wonderful thing. Indeed no film-maker working in Europe now is as capable of turning birthday gatherings, garden parties or poolside barbecues into thrillingly sprawling canvases of human virtue and vice as this 39-year-old rising star. From a riotous water fight in the Berlinale Golden Bear-winning farming drama Alcarràs to a foul-mouthed dinner table singalong in her new film Romería, Simón directs kinship meetings with the attention to detail that other film-makers may invest in action sequences or dance routines.…