Wrists aren't just for decorative bracelets in Summer — they're also the place for an Insect Repelling Superband (£4 for 4-pack). There are bands from different companies, but I can personally vouch for the Superband, having used it for my last 5 trips to Cyprus — my daughter has never been bitten, and I've only suffered one bite (having been covered in them on previous, Superband-less holidays to Greece). My Superband-less SO got bitten to bits.
It contains geraniol, lemongrass, and citronella oils, is non-toxic, DEET-free, and waterproof, and lasts up to 200 hours. For children over three.