I'm a young professional living in the South Loop with a great deal of past babysitting experience (and could honestly use a little extra income to help pay off student loans). If you are still looking for an occasional babysitter, I'd be happy to be considered (though I'm not certain how it would be best to be in touch as I'd rather not post my personal contact information here).
Seconding Lizzys comment. I'd love to be of help, I have past nanny experience and babysitting experience as well. I'm 27, recently married and moved here from New York, having grown up in Florida. I'm in the South Loop and nannied for a family down here for about 6 months before finding full time employment. I miss the interaction with the kids and the extra income it provided! Let me know how and if you'd like to get in touch.
I am newer to the South Loop neighborhood and have many years of babysitting and nanny experience. I only have one family I occasionally babysit for now and would love to build my network back up for back up babysitting. I am a 26 year old professional, but am available on certain week nights and weekends. Feel free to email me at email@example.com for any parents who need another back up.