I work with under 5’s and have done for 10+ years your best bet is to just be consistent with how you respond. Right now the smacking is just like when babies explore with their mouths and everything goes in there! Now it’s everything gets a smack to see what it feels like / sounds like etc. If you want to discourage I’d recommend: - a clear hand signal /gesture eg Pam facing the baby ✋ - a clear word or phrase ‘stop that’ - moving the child away from where the smacking was occurring , but then acting as though it didn’t happen This way baby isn’t being punished they’re just being taught what you think is a wrong behaviour and eventually they will learn not to repeat it. They might go through a ‘cheeky’ phase of doing it more but eventually will get bored of being moved away each time from what they’re playing with. Just be careful with what you say as if you say ‘don’t smack’ what babies actually hear is ‘smack’ as they’re more likely to listen to the last word not first x
Generallly at this age babies are interested in reactions and aren’t able to distinguish between a good or bad reaction. So best thing to do is keep the reaction small and consistent. With this I would say no thank you or whatever phrase you want and then redirect the behaviour by getting them interested in a toy or whatever.
Following for advice that may help with my son but for biting 😅