I tried using greenscreen for a variety of portraits (headshots, kids, seniors, sports, etc.) and found the results to be terrible. The problem is, in confined space where you can't put a lot of distance between your subject and the background, the greenscreen will cast a bit of reflection back onto the subject, and a faint green hue will permeate the edges of their arms, legs, etc. It's impossible to remove it completely, and it will ruin a good shot. Especially when shooting babies (who take up a small space!), you could visit a fabric store (I use Joann Fabrics) and find sales on fabric. For as little as $5-$10, you can get a couple yards of fabric to use as a background. My more frequent option is to simply shoot people against a white paper sweep. Don't light the background, so it goes a bit gray in the photo, and then using the selection tools and options in Photoshop CS6, you should have no trouble getting a clean cutaway and then laying in a new background (as in the attached examples).
HOSTED PHOTO
please log in to view hosted photos in full size.
HOSTED PHOTO
please log in to view hosted photos in full size.