I have a minor child from a previous marriage. He is still incarcerated and has minimal income from his prison camp job.
Take a look at page 7 of publication 501 http://www.irs.gov/pub/irs-pdf/p501.pdf. You may be able to file head of household if you meet all the requirements (but you may not file single). Nevertheless, it may be more beneficial, tax-wise, for you to file married filing joint.