If you make over $400 on a 1099-MISC, you are required to file a return and pay your self-employment tax on that income. The fine is 10% of the tax due, plus interest.  

You have to file a return claiming income for the year in which you earned it - that is, the year shown on the form.  Since this is your earned income, it will not affect your mother at all.  

Remember to mark the box "Someone else can claim me" when going through your TurboTax Personal Information interview.