You could tell her

You could tell her that someday she'll be standing at a sink
scrubbing the three-day old pot, thinking about a boy
she used to know but doesn't dare mention.

She wouldn't believe you, of course. The earth knows the sun
is doing all the work. The earth knows the sun does the circling.
Her life will be different, she knows it. You want her life to be
different from yours, but she doesn't believe that you could want
what she wants. Best keep the givens of her future to yourself:
the lost boys, the yeses that should have been nos, the doors
clicking shut and locked behind, the regrets accruing interest.   

You want the ones who will fall in love with her to stay in love
with her, to fight for her even when she fights for flight. You 
want her to settle for the more that comes with less, you want
her to know her limits and her hubris, you want her to become
the lawyer, the astronomer, the doctor. You want her to save
herself long before she ever needs to, with statutes and numbers
and microscopes and insurance forms. Let all the beauty come
as a surprise, you think. Let her unlearn expectation. Let her be
washed clean as bone, stripped bare and bright, again and again.