Potty training twin boys- one is ready, one might not be 😝

Did anyone potty train one twin then the other? They will be 2.5 yrs next month. One is showing all the signs of readiness the other maybe 1 sign. Idk which is worse- one holding the other back or one not catching on and needing to revert back to diapers 🫣

Also any advice on training boys is greatly appreciated (I have a daughter and she was super easy)