How does a "new parent" know more than me?

[apples and bananas]

Do you think the baby has developed an allergy to the formula? Maybe she doesn't want to eat and mom's forcing it at home. It could explain the throwing up.

Aside from that... i think we all do things or don't do things that parents request and just don't talk about it at the door. For example... the nap! Haven't we all had parents that say 'don't let johnny sleep for more then an hour otherwise he won't sleep through the night' And when we leave him to sleep for 3 hours and the parent shows up and says... how did he sleep? Our answer is always "he had a great nap"

Sometimes we know what works best for us in our house and it can't always be the way the parents do it.

My advise is to give as little info as possible to her at pick up. And really try to start controlling the environment rather then taking orders. Sounds like she's speaking to you like you're the nanny. A common misconception.