MIL and Halloween

So I get along fine with my in laws. But I have had problems in the past with them taking over holidays/birthdays. I'm currently pregnant and our second child will only be a month old + a week or 2 come Halloween. My husband has to work on Halloween but I will be off still on maternity leave.

My MIL just texted me this:

A part of me wants to tell her no but honestly how am I going to celebrate Halloween with a newborn (1 mo) and toddler (18 mo) by myself. I do have a double stroller and our neighborhood is talking about putting together a truck or treat so I might be able to pull that off. I don't want to be rude but they got her last Halloween and bought her a costume when I had already made her one.

You only get so many Halloweens with your children before they start to do their own thing and I'm sad to miss it. My husband works night shift so he is still sleeping so I have not been able to talk to him about it.

Should I just let them take her for the night or invite them to come to the possible trunk or treat in our neighborhood?