@DemelzaPoldark
Why could your mother not download the pics she wanted (off facebook,) and go to Boots photo-kiosk machine and print them herself. (And then go to Wilkos for the photo frames as they are much cheaper than Boots for photo frames!) I do this with my adult children, when I see pics I like on their facebook.
I have a few pics of them in my 'family corner' in the dining room. They do know BTW as I ask them first, and they are perfectly happy with it. I also repost a few of their pics on my facebook (so my friends can see them.) Again, I ask them first. I would never take the pics and print them, or share them on facebook without asking...
I think you are being a bit precious and unreasonable, as it is perfectly understandable for people to want pics of their grandchildren (and adult children and partners/spouses...)
Why were you so reluctant for your mother to have pics of your kids?
I do think it was a little bit weird though, for your sister to print off pics of your kids and give them to your mother... Maybe because you weren't doing it, she turned to your sister to see if she would do it. As I said though, I still don't understand why your mother couldn't do it herself. If she is tech-savvy enough to use the internet and facebook, she is tech-savvy enough to download the pics, pop them onto a USB, and go to Boots to print them.
As an aside, I know a few people who have adult children who behave like you OP - getting annoyed easily by simple, normal, understandable requests from their parents (like pics of the grandkids, more than one phone call a month, to be able to see them more than once every 1 to 2 months, and to be able to be in their lives more without being made to feel like they are nuisance/intruding in their lives...) It's very hurtful for the parents whose (adult) children treat them like they are a nuisance..
I know SOME parents/mothers especially, can be a bit annoying an demanding, but some just want to be part of their adult child's life and don't want to be pushed down to the bottom of the pile and treated like a nuisance.
You are coming across (a bit) like one of these adult children... And BLOCKING your mother, and sister when they have done nothing wrong?! Very petulant and childish.
awaiting a massive drip feed......... 