A COUPLE dramatically rescued when their car plunged into a canal have been found dead at their home in a shooting horror.Police are investigating whether Bob Seddon, 68, gunned down his wife Patricia, 65, before killing himself.They were found dead by police at their semi-detached home in Clough Avenue, Sale. It is understood Mrs Seddon had suffered gunshot wounds but it is not yet clear how Mr Seddon died.Just four months ago, the couple were travelling in a hired BMW driven by their son Nic when it plunged into the Bridgewater Canal in Timperley, Altrincham, and sank.Mrs Seddon's heart stopped as Nic and firefighters rescued her, Mr Seddon and grandson Daniel, 16, from the submerged car. Mrs Seddon survived after being resuscitated at the scene. As forensic officers combed through the three-bedroom home, friends paid tribute to the couple, who were married for 46 years.Friends living on Clough Avenue had become concerned for the couple's welfare after seeing no sign of movement from the house since Wednesday. It is believed Mrs Seddon had recently been experiencing failing health after suffering a brain haemorrhage last year and required around-the-clock care from her husband.Mr Seddon, a retired airport worker, suffered a heart attack shortly before that and is believed to have recently been put on a course of anti-depressants.Four years ago, the couple's 40-year-old daughter Lesley died in their family home after suffering an epileptic fit. A police spokesman said inquiries were continuing.