After you have replaced the door knob on the shed and unlocked the shed(key under the welcome mat) you can access the sheds contents… these include a watering can to water the flowers (after you have repaired the hose) and fire extinguishers. In case of fire simply head out to the shed and grab a fire extinguisher, your little guy will take it from there. Don’t forget to praise him/her for a job well done.
Also you can use the following cheat.
When any appliance is on fire (cooker, dryer, etc) then just quit the game and when you restart the game again you have no fire and you can carry on with your work without the little guys screaming about the fires.
