Shes always asking me for baby stuff

I don’t wanna sound selfish but oh my gawddd my sister-in-law always asks me to let her barrow stuff (my baby stuff) all the time and we live in the same area, a few steps from each other. Our babies are four days apart so they have the same months. Well when ever she comes to my house she will be like

“Hey, do you have a bottle I can have that you don’t use”?

I use all of them but I still have her one

And another time was

“Hey, can i barrow my shirt for my baby?”

I looked for one and I gave it to her

Another time

“Hey can I barrow a swaddle”

I was like sure I gave her one

I don’t do it for her I do it for the baby we are all family here but I’m just like

Ohh my gawwwwwddddddd

Do moms no longer carry diapers bags?

She lives a few steps from me why can’t she just go to her home and get whatever she needs. I have two kids I gotta make sure when ever I leave my house that I have everything. I pay for the things my kids have it costs me I know she’s not going to return anything. I don’t like asking people for things. And I don’t mind her asking once here and there but alll the timeeeeeeeee it’s like dam lady. Why carry a diaper bag if you’re always going to forget everything.

She has everything she asked me for and way more stuff then I do like dude

What should I do or tell her? If she asks me again? I don’t want to sound rude or selfish.