SJS, it’s exactly as Mod-80 said.
Girls and boys ARE different, period.
SJS, so for a big bas mitzvah bash do you think girls would want to become boys? Well if they don’t and they won’t act like boys nor perform religious obligations like the boys do, then they will not have a big celebration as well (nebach, nebach, poor girls , my heart bleeds for them, lol). It’s a package deal.