Go to a commercial photographer: pay him or her to take some photos of your baby. Take those photos to an agency specialising in children.
If your kid is as cute as you think they are they'll put him/her on the books...
Many parents pay photographers to take photos of babies and children. Right now I'm offering TFCD while I build up my portfolio. Because there are enough parent's out there glad for this I wouldn't consider paying.
So the only real market I would assume is going to be advertising. Both the good and bad news is it will be a high turn-over market so they'll be looking for new babies all the time.
Just email an agency like scallywags some regular snaps of the baby. They will take a look and invite you in to meet them if they think the child has potential, as I understand it good child agencies do have fees, unlike decent adult agencies (can't remember why now but it was a good reason). The first thing an agency look at is the child's looks, but more important to them is it's personality, a happy, constantly smiling baby can be known to be very busy because they are easy to work with. Don't waste money on getting images done for an agency (only for yourself and family) as the agency usually prefer personal images in the first instance.
okay thanks for the advice i will look at those sites.. im very honest with my babies looks when she cries shes the grinch.. thats rare though she always smiling and talking big brown eyes long eyelashes beautiful long thick hair her ears dont stick out, i know shed be great, il figure how to post a picture maybe