I bought this red cross pacifier thermometer for mine (along with the other regular ones)
http://www.toysrus.com/product/index...ductId=2449557
I took the temperature using both this one and rectal and the pacifier is quite accurate.
The trick is to make sure you hold the pacifier in place.
If your wife is a new mom she could give it a try since its likely that she will want to check the temperature everytime the baby "feels hot or looks sick," at least the poor thing won't have a thermometer on his/her booty 24/7. You can always do the rectal if the temperature is actually elevated.
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