Should I tell my boss I want to move up?

I was in a managment position in another company, decided to resign for my son (very long hours) and recenthly I changed job fields. Now am I at another company, entry level, terrible pay, etc. And my new boss is sweet and great but I always express to her that I want to move up. It has even slipped out of mouth changes I would occur whenever given the chance, etc. She seems enthusatic about my wanting to ventur up (not to her position but in her boss' position)..I am headstrong in my training, completing all my tasks and usually having a lot of time to spare but is this being rude or impoliet. Honestly, am I just being a b! about the whole thing?