Something maybe everyone of us share from our childhood (and our fathers and maybe our grandfathers... well, our grandfathers don't, almost certainly all of them grew up in very hard labor conditions, maybe in a farm or something like that) is that our parents tell us we could be whatever we wanted to be, but I think that's a mistake, a big one.
Foots on the floor, the real thing in our world is that most of people live a life full of frustrations and despair, with just a few beautiful experiences that makes life worth living. As a consequence of that gentle error of our parents, those who decide to prepare for future and study, many times choose professions that probably they'll never use due to reasons related with the working market (I'm not counting engineers and coders); we arrive to a world already full of talented people doing things, and the only hope we could have is that this people will die someday, and will have to be replaced, and maybe, with a bit of luck we'll be there, ready for the show.
Maybe we shouldn't say our kids they could be whatever they wanted to be in life and start to showing them detailed analysys about working opportunities in their future.
Einstein, Mandela, Washington, Ghandi, Khalo. Have you hear this names? Most of us recognize them as important ones, right? Well, if you've heard from them is because they belong to the little group of people that made big changes to our world, and I'm pretty sure of something: no one tell em that they could do it, in fact, they did it against the rest of the world (in many cases including its fathers).
One last advice: specially don't tell your kids they could someday be astronauts, it's the worst laboral scenario. C'mon, astronaut, really boy?
Let me know in the comments what do you think about human's future, child raise and my poor language skills.