MIL like to hoard things she buys out of spite

I'm 32 weeks and 2days and I started to wash the baby's clothes and finish the final touches in the nursery(nesting I guess). I called my MIL and asked her to bring over the clothes she bought for the baby and also the crib bedding set that she bought so I could wash that stuff too. First she tried to tell me that baby stuff doesn't need to be washed then that she wanted to keep them at her house until after the baby shower. I hate waiting until the last minute to get things plus my baby shower will be after Im already 9 months and the baby could come any day before or after that. I feel like she only keeping the clothes and stuff because she keep hoping that she will be able to keep the before she turns 3 months. Which is a rule that I've set since my first child. I want to tell her to just keep her 💩 and I'll just by my own bedding set since that's the only thing thats making the nursery incomplete.