How can i get the money back?

-My mom, who isnt my legal guardian, as of June, owes me 6000, 4000 of which was from 4h checks that were signed over to her when i was 8-13, can i get the money back? she said shed pay me back on my 16th bday, on august 6th, but if she doesnt i need to know what i can do, and what will it cost me?Lawyer, 200-400 $$$$$$$$$$