SIL ignoring me

Okay so I 100% believe that people are not required to reply or answer but my SIL told me that if I needed help she would come to my house and help with the baby. Well I asked her to come and she said yes but then the day came and she never showed up or replied.I just though okay whatever she’s probably busy. Well that same day I went over to my MIL to get some stuff from her and I text all my SIL to let them know if they wanted to see the baby I would be at their moms house. 2 answered and said they would come. I called the one that was suppose to come over to my house and the call went to voicemail after a few rings. When my mother in law asked if I had even told her I said yea but she didn’t answer my text or call. She called her and my SIL answered right away and said she wasn’t doing anything that day. I really feel like she ignored me on purpose. I didn’t do anything to her and I don’t know what to do. Do I just brush it off or do I say something or what? It really hurt my feelings because I needed help that day so I could organize our new house and she told me she would come but never showed up. Sorry if I’m rambling.. I don’t have anyone to talk to about this. If I bring it up to my husband he will just say to ignore it. Am I overreacting with being hurt by this? I guess I should also mention this isn’t the first time.. I got her a job a few months back and she went through the whole process and then never showed up for training. They even offered her a higher pay than what they normally do because of her experience and knowing me.. I literally can’t sleep because it’s bugging me.

** I decided that the next time I need some help I’m going to make a group chat with all of my sils and ask who can come by to help me and if she replies that she can I will be like “are you sure you’ll show up this time” or something like that. I kinda wanna be petty but I’ll leave it for now. Thanks ladies. I thought I was being dramatic.