Should I be upset - sole carer and I find out older sister has Long Service leave

I am the 2nd youngest in my family and the sole carer of my mum for many years. There have been times when I have been nearing breaking point as I have health issues myself. I have an older sister who lives 11 hours away and she works full time. She will phone me to see how I am doing and how mum is doing but she has never taken time off to help...
In fact she phones mum once a fortnight or every three weeks and the call is brief.
I was talking to her the other day and she said that she can take PAID long service leave now(this has been in action for a while.) I waS Shocked! All the times when I had been snowed under with mum in and out of hospital..all those times when I wanted to take a break for a holiday...I asked her previously for help but she said she had her work and couldn't leave..

Should I be upset?

Did you ask for help when she mentioned she had leave?

Should you? There is no obligation to be. But I would be rather miffed. It seems from this post and your other that your family seem to have different values. You look after your mum, problem solved. For them anyway. They probably don't think too deeply into it, because it is just easier for them to live their own lives and leave you doing what you do.

Can you ring your sister and ask if she could come down for a week or so and give you some time to take a break? Lay it out plainly for her - you have cared for your mother for many years without a break and would like to have a bit of down time.