How would you handle this?

My firstborn (3) is awesome with her brother (7 mo) overall. The only issue is that she is constantly in his face either trying to play with him or trying love on him. Since he was born we have tried to teach her not to be in his face and we have tried to teach her to give him space and just a little bit of love here and there and not to get in his face or mess with his face while she plays with him but I seriously am saying a million times a day to give him space or get out of his face. I’ll tell her and she’ll say ok and then it’s like she forgets literally a minute later. I know that she is trying so hard to get his attention and to make him smile and give him love so I’d really hate to discipline her for that but this poor baby has to deal with his constantly smothering him and especially his face and it’s driving me crazy and I just get more and more frustrated throughout the day repeating myself over and over and sometimes do have to use discipline and then she will just leave him alone, it’s like she can’t interact with him without doing it. I notice she does it the most when he is playing and not looking at her so she’s trying to get his attention. She loves him so much and is so sweet to him but this one thing is super frustrating. Should I just ride it out and keep reminding or start using more discipline after the first couple reminders or any other advice? I just don’t want to hurt their relationship at all but disciplining her for not being malicious. We’ve had talks about how it’s not fun to have someone in your face all the time and I’ve showed her by “smothering” her with love as an example and she doesn’t like it lol and acknowledges that it’s not fun but then forgets very quickly.