My one yr old is walking with a limp..he doesn't seem to be in any pain..there is a little swelling on his left knee..what could this be?

Hmmm: Could be anything from your child hitting his/her knee on something to transient synovitis to septic arthritis. Usually nothing serious but if it persists or your child has a fever, have him/her evaluated ASAP.

Limp: First let me say that your child is a fast walker if he is just 1 yr old and has been walking for a while. To answer the question, maybe he injured himself when he was walking around and possibly fell (kids this age are clumsy)