Hampton Bay Wireless Doorbell Extenter Kit. This is so easy to use and is convenient. It wirelessly connects to your current doorbell and you can plug it into the hall where you can hear it- the end of the hall, the bedroom, etc. and away from where you want it quiet, like the babys room.
These were $40 each and I bought more than I need. Only 1 is used per house. So it's yours new in the unopened container for $10. You can stay in the back of the house and hear the doorbell!!