Am I wrong for being a little upset?

I am set to get induced on Tuesday the 23rd with my second child. Originally, my sister told me that she would watch my daughter while my husband and I are in the hospital (this has been the plan for months).

Now she is complaining and getting mad because she has to study for her exit exam for nursing school and has a bunch of homework (that she has procrastinated on) and is annoyed that she won’t be able to with my daughter or that it’ll be extremely hard. What makes me annoyed is that we’ve had this planned for months now and she’s known for three months she has this exam to take but is fine with making time to talk to her long distance boyfriend for hours but now less than a week before my induction she’s all of a sudden having and issue with studying and my daughter not being able to give her “time”. First of all, I want to add that my daughter is 3 and knows how to self entertain. Second of all, I know it’s possible to do it because I passed nursing school and my nclex while taking care of my daughter so and that was for 2 years not 2 days. But I’m trying to be understanding because she doesn’t owe my anything.

Then when I asked my mom if she’d watch my daughter on Thursday-/Friday (if we aren’t home yet) she got annoyed and said that my husband can come home and watch my daughter while I stay in the hospital with the baby. I told her no that’s not an option for us obviously unless I was in there for longer than anticipated. She told me I was being ridiculous and that she gave birth to me without my dad being there and blah blah blah. I just thought “good for you, doesn’t mean I should have to go through the same thing” + it’s not like my dad was at home taking care of their other children, he was working or else he’d be fired. My mom doesn’t work but does have fibromyalgia so again I’m trying to be understanding cause she doesn’t owe me anything.

Lastly I feel like I can’t ask my mother in law to help watch my daughter because she unexpectedly lost her husband a couple of weeks ago and I just don’t want to burden her with anything because she’s grieving but of course my mom is telling me to get her to do watch my daughter. Would that be wrong or me to ask?

I’m just so stressed. What am I supposed to do? Am I being unreasonable? Am I wrong for being upset.. 🥺

Edit: I also want to add that my husband and I currently live with my parents and so does my sister. So it’s not like someone’s having to stay somewhere else or go anywhere.