24 minutes ago Joshua Askew, South East and Helena Wilkinson, News correspondent Sussex Police The three sisters, seen here with their father as teenagers, died in the sea An inquest has opened into the deaths of three sisters in the sea off Brighton beach. Jane Adetoro, 36, Christina Walters, 32, and Rebecca Walters, 31, who were all living together in Greenford, London, died on 13 May in what police called a "terrible tragedy". At the inquest at Brighton & Hove Coroner's Court on Friday, senior coroner Penelope Schofield offered her condolences to their father Joseph, who attended via a remote link. Addressing him directly she said: "It must be a difficult day for your family. "The loss of your daughters in these tragic circumstances must be unbearable." An investigation by Sussex Police into how the three came to be in the water is ongoing. Officers were satisfied there was no third-party involvement in their deaths, the court heard.…