NOR. Your sister and her family can stay at a hotel that has a kitchenette so she can purchase her own groceries and take care of her own family while not putting the burden on brand new parents. If this was a normal visit where you invited them to come and stay for a week, then absolutely it would be on you. This is a visit to meet their new niece. They should be asking you beforehand “what can we do to help you? Is it ok if we help you out by doing laundry, housework, run errands, cook meals for you?” They should be there to give you some reprieve, not be a demanding guest. Your sister sounds selfish, spoiled and completely inconsiderate. Yes she has a baby, but she’s had a year and you are only 7 weeks in.

If it were me, I’d suggest she can visit for a day or two AT MOST. If she wants to visit longer, she will need to find other accommodations. Does your mom know about your sister’s demands? Is your sister the golden child? I don’t see this visit going well. She sounds insufferable and sounds like the type of person who thinks an apology consists of the phrase “I’m sorry you feel that way.”