My little sister is stuttering a lot recently. What are some things that helps you guys when you're stuttering?

My little sister is stuttering a lot recently. What are some things that helps you guys when you're stuttering? Hi, my (15F) little sister (6F) has been stuttering quite a bit recently. It's usually from over excitement and trying to get her words out all at once, but also sometimes from being nervous. When i notice her speeding up a lot, i'll gently remind her to take a breath and slow down, but she always ends up stuttering after a minute or two. I wanted to know if there's anything that stutterers find/found useful to help reduce the stuttering. I also wanted to make sure there's not anything i'm doing that could be making it worse (like, i know not to interrupt/guess her when shes stuck in a stutter cause that just makes it worse). Im not saying i think it would be easy just to 'cure her' at all, i know that. All i want to do is find some ways to make sure she knows she is supported and ways to help her reduce her stuttering, as i know it really annoys her too.