Nothing wrong with correcting other children in a kind way. Also, keep encouraging her to be kind, but to also speak up for herself. She can use words like, stop, and learn how to ask you for their adult, so their adult can address it.
https://www.pbs.org/parents/thrive/how-to-raise-kids-who-can-speak-up
@Hannah it’s not a full solution but I’ve found @mrchazzmrchazz content on TikTok/Insta to be helpful for setting boundaries. I really like this short video for example (https://www.tiktok.com/t/ZT8N3tNwH/ or https://www.instagram.com/reel/CrRv9vurgIj/?igshid=MzRlODBiNWFlZA==) I adapted this approach but when my toddler had fewer words I served as her mouthpiece. For example I would look at my toddler’s reaction to the other child and tell the other child “It looks like she (my toddler) doesn’t like that when you push (or insert other action here) her…” and if necessary provide alternative directions on what they can do instead… something like “you can have a turn when she’s done/you’re welcome to play over there/you can go around/there’s lots of other places to play here/this play equipment is for everyone so everyone can take a turn” etc as examples depending on the situation. I hope this helps!
Another example: “oh, you wanted to use that? It looks like she’s (my toddler is) still using that. When she’s done you can have a turn.” Or in situations like waiting to use a slide and older or more aggressive kids keep pushing past and then my kiddo finally gets to the front of the line and can take her turn, instead focusing on praising the actions she did well and vicariously modeling to other kids “wow, that was really hard to wait but you did it! You were so patient waiting for your turn/great job waiting for your turn. (And then assert!) Now it’s *your* turn! You can do it! Go ahead! Let’s go! Alright! Yay!” And also praising the thoughtful kids who wait or offer her to go as the less assertive one. “Thank you (for waiting!)” etc.
Also this https://www.instagram.com/reel/Co-_GK0PteD/?igshid=MzRlODBiNWFlZA==
I love this! My 18 mo doesn’t have this much language yet though so she can’t advocate for herself with words yet