a question for the Mormons

[TalenaGor]

So the background to this is my mother passed away from covid in December just before Christmas.... She was somewhat Mormon although not really practicing and throughout her life she's been several different religions... I guess she never got done exploring her beliefs maybe who knows... In any case she did not give me any sort of instructions beyond cremation as to her wishes....

Her brother however and his family have been Mormon their entire lives very devout.... Her brother passed away a few months before she did

her brother's wife, My aunt, just texted me and asked me if she can seal my mother to her parents (my grandparents...)

I have no idea what this means other than she said it means they can spend the afterlife together.... I am an atheist so the whole thing is rather awkward for me to even think about

As far as I know my grandmother and my grandfather were not Mormon .... But they have apparently been sealed in the Mormon church after they passed, by my aunt and uncle....
My great-aunt is also going to be sealed.... She is also not Mormon.... She's also already passed....

Is it normal to perform this ritual upon people who have already passed regardless of their religious affiliation? Regardless of whether or not they asked for it?

She's asking for my permission.... I'm not sure how I feel about it on one hand I think what could it hurt but I also don't know if there's any actual real world ramifications to this ritual.... Is there any legal implications?

And then I wonder would they be sealing me after I pass? Knowing I'm atheist? Assuming they would not.... Then are they in their mind separating me from my mom and my grandmother and my family?

I just feel really strange about all this... I would appreciate some wisdom from du...

Edit to add: My mother and her brother were Not very close.... She didn't speak to her father for most of her life.... I'm not sure she'd want to spend eternity with them lol