Babysitter/nanny bring her Hametz meal in my home?

Question

Can the babysitter/nanny bring her own lunch into my home on Pesah that is Hametz? example a container of macaroni. I can reasonably expect her not to make a mess, and there should not be any crumbs that can be a problem. She already keeps her tupperware separate and washes it when she goes back to her own home. If the answer is no, end of story. If the answer is yes, I can tell her no Hametz that can cause crumbs as I mentioned earlier. Your responses are always appreciated, and thank you in advance. Sander Silvera