Some kids will take a dummy, others just won't.

I've had two dummy dependents and was trying to introduce it to DD2 (cos I figured I could at least take the dummy away)....but she ain't havin' a bar of it! She's a two middle fingers kid. I have to say - it's far easier in the middle of the night.
With the older kids I just kept putting it back in....they got the idea lol.