Hi Im NEW, Please HELP!!!!!!

Greetings:

I've been reading posts form this blog for about 6 months now, and is the first time I write one.  Here's my situation:

I am from Puerto Rico and as you may know (or may not know) I am a US Citizen.  Thing is, I have an audition on April 25 in a music school.  If I get accepted, then I am planning on moving to Brussels.  THING IS, I am not alone.  I have an 8 month old baby and live with my partner (not legally married, but living together since 2010).

The school says they help foreign students with visas but, what are my options with my child and partner?? Does the Belgian government recognizes not married couples with children as a legal family??  What are my options??

Also, I've been reading in the Belgian Embassy about Student Visas.  It says something about finding a sponsor; someone that will be "in charge" of me and my expenses.  I've been trying to find if there is an amount of money the Belgian government asks like from a bank account evidence or something.

This is REALLY IMPORTANT TO ME.  I need to move forward with my life and family and really want to move to Belgium.  I think is the best option for me and my family.  Any advice of help will be much appreciated. 

Thanks!!!!!!