Mothers are complicated

I am so depressed and worried. I was supposed to work at the school thrift store today. My mom was supposed to watch Lily. We had it all arranged a month ago.

And then something happened which I am completely in the dark about. Out of the blue, my mother called last night and said she "had something she had to take care of" today and wouldn't be able to watch Lily. That was it. That's all I got out of her before she hung up. This is not like her unless it's really about my sister who is constantly messing with everyone's lives. That's what it was the last time there was a mystery. Everyone else got dumped to deal with my sister's unending parade of crises.

I'm not bitter much, but I am worried about my mom. She's either not home or not answering her phone and either way it's weird and unsettling. I usually talk to her 2 or 3 times a day.