Yeesh.... so do you think it's that she CAN'T, or that she WON'T/doesn't know how?
Because if you feel like she lacks the ability, I think it's time to make more of an effort to tell the parents that it's NOT normal for her age.
However, if you are seeing progress in her development, I guess just be patient. Sadly, it sounds like you will be the one teaching her all these fun things.