MIL hoarding my sons pajamas

I know this sounds weird af but I’m kind of bothered about this

My MIL and my mom used to watch my son over the summer. (10months at the time) Everytime id drop him off, I would send 2 extra pairs of clothes. In case of a blow out, or getting messy playing or whatever. Sometimes I didn’t even replace the outfit in the bag right away, so I wasn’t really keeping track. And he had a ton of clothes anyway so whatever. I would notice an outfit missing here and there, but sometimes I would just think, oh I guess I took the outfit out, or maybe it got dirty and whoever had him washed it for me or threw it out or whatever.

About 2 months ago, I was at my MILS for dinner. She told me her bibs were in a closet in a spare room. I noticed in the closet a bunch of his clothes! Not really a big deal, I figured maybe she kept them there in case he needed a change of clothes, but I always sent him with extra so I was like well she’s kind of weird so I let it go. Most of it was just regular onesies and pants but there was one shirt that i absolutely loved on him, and I had gone crazy looking for it, so that kind of pissed me off, but didn’t matter at that point bc it didn’t fit him anymore so whatever.

Last week, my son slept over since his cousins did. Sent him with 2 pairs of pajamas. One yellow pair and one blue pair. Comes home with the yellow shirt and the blue pants. I ask her about it, she tells me that was the only thing in his sleepover bag. I know that’s not true because I wouldn’t have sent him with only one pair, and not a mismatched one.

So tonight we go there and I’m all ready to steal the pajamas back. I go to the closet to “get a bib” and they weren’t there! Soooo I know I shouldn’t have done this but I really wanted them back so I went into the dresser. The dresser has a bunch of his old swaddles, more of his clothes, and the pajamas.

I wanted to take them back, but I didn’t want her to know I went thru the dresser. I know I shouldn’t have, but I know it’s not were she keeps her clothes, it’s really just winter stuff, blankets and stuff she steals

If she kept the whole set I wouldn’t have cared as much, but since she took the blue shirt and yellow pants I now have 2 pairs of pajamas to replace. And he doesn’t have many pairs so they need to be replaced. I just got them for him for Christmas.

We left pretty late, and I said “wow I really wish I had pajamas here for him so I could just dress him now so he can go right to bed when we get home” and she was like yeah I’m sorry no pjs here.

I know she didn’t forget them, bc this was literally last week. And I asked about them the following day.

Do I take them back next time, or let it go??