Rocky with Melody (20 months, left) Elsie (three, middle) and Joe (five, right) (Picture: Triangle News) Rocky’s recovery has astounded vets (Picture: Triangle News)Matthew explained: ‘He likes messing about with the younger ones – he sees himself as one of them.

The long-running series in which readers answer other readers’ questions on subjects ranging from trivial flights of fancy to profound scientific concepts Does my cat purr when it’s alone in the house? Does my cat purr when I’m not there?