My 2.5 y.o won’t let my 1 y.o do anything and it’s heartbreaking. Any tips?

[gensys]

Basically I have a 2.5 year old and a 1 year old. They’re both freaking adorable and genuinely adore each other.
My eldest has been the best big sister, always happy to share and do things together. Recently she will sometimes catch wind of my 1yo playing with a toy or reading a book and will go over and claim it. It is so heartbreaking because my 1yo is just left there looking so confused.
Of course, we still let my 1yo play with the toy or book and explain that she had it first, but my 2.5yo still loses it. We also explain that you can swap a toy or book which sometimes works which is positive.
It doesn’t happen all the time and I understand it’s likely just part of being a toddler but does anyone have any hot tips?

 

[darstone]

@gensys Consistency is key. Never waiver. Don't allow either child to snatch toys from the other. Very calmly, return toy to first child and say "they were using that. We don't snatch toys/books/items." And empathize and comfort the upset child who can't snatch. "It's ok to be upset. We need to wait our turn."

They should both also have special individual toys they don't have to share that is kept in separate spaces.