• Colour: White mouse.
• Born: around 1974
• Died: around 1975
• Age: perhaps 2 years
  
• Gender: Boy
  

Lived with Mike’s family. Cromwell was a nice little chap and star of at least one of Mike’s school’s summer fayres, featuring in the local newspaper. Cromwell got a bad skin condition and needed cream to try to help. He may have had a companion for a while, but unfortunately no-one can remember his name just now.