I have a much loved 8 year old cat . Lively , bright eyed , eats well . The last few weeks her poos have become runny & absolutely vile ! If she uses the tray at night I literally have to get up , clear the tray & open the windows . Mostly she goes once a day but sometimes she will do 4 or 5 small runny offerings . She is on Purina dry food . I'm guessing a trip to the vet is on the cards but any other ( less expensive !) advice first would be appreciated.