The Tricksters
by Margaret Mahy (Orion, 1986; CollinsFlamingo, 2001)
A supernatural coming-of-age novel. The large family cast adds a chaotic, disorientating element but also a homely verisimilitude plus, it turns out, a mystery hiding in plain sight (masquerading as a smokescreen for the overt, speculative goings-on!). Slow-building but worth committing to.