"nothing on earth could have me in the situation my sister is in."
Well, of course, there are biological differences between the sexes ;-)
But you're talking about sex, not gender. Gender is, according to wikipedia:
"A socio-cultural phenomenon that divides people into various categories such as "male" and "female," with each having associated dress, roles, stereotypes, etc."
In very early human primitive societies engaged in the day-to-day struggle to survive, roles were doubtlessly more restricted according to one's sex for practical reasons; child-bearing (with no contraception available - a tool developed later by humans to allow us to control our own _biological_ behaviour) would naturally dictate a more sedentary role for women.
But social behaviour is not governed by biology; it is shaped explicitly by our conscious self-awareness. Sometimes this has a subconscious undertow (which can be consciously counteractable once it has been identified), but this too is socially shaped (see my long post in response to giraffedata).
All our actions (even the most basic, think about eating food for example: animal feeding compared to human dining, with all its intricate rules, meanings and varied contexts) take place in another dimension when we carry them out compared to our closest primate 'relatives'.
Chimps and gorillas probably get very close to the self-conscious border and may temporarily pass over it; passing, for example, the 'mirror test' (although not without 'practice'), and a gorilla was spotted in the wild  taking 'measurements' in water using a stick, indicating perhaps a sense of 'I', wondering whether the water was too deep to wade into.
(Assuming their physiological make up allows it, the fact that gorillas, and many 'higher' primates, with a few rare examples, can't learn to swim is a pertinent example of the inflexibility of their behaviour - even when such a simple skill is involved - compared to ours, btw. Many other 'stupider' non-primates can swim, presumably as a result of, in their case, a genuine biologically 'hard-wired' 'instinct'.)
But apes (and indeed all other animals) are characterised by their inability to stay in the self-conscious realm _permanently_ like we do; there is a fundamental passivity in the behaviour of other primates, behaviour which has not altered over millions of years, and which, without our intervention to teach them tricks and 'sign language', speaks of a lack of sustained, conscious, self-awareness - a lack of any intentionality which might allow them to understand and shape the world around them. While they exist through their lives, our lives are narrated through an explicit interaction with others and the world around us within a baroque, many-layered social framework of our own meaningfully-interpreted invention. No behaviour that arises out of this can be realistically compared to that of even the most intelligent chimp, who cannot be capable of grasping a socially-determined concept such as gendered behaviour, with its 'associated dress, roles, stereotypes, etc.'. Nor can the way we live our lives at all be crudely accounted for by any biologically-determined features, like the comparative size of areas of the brain.