Relax. I have four children and they all progressed at different rates. When my second child was one year old his older brother was 3 years old. He didn't have to talk. My 3 year old did all the talking for him. The other thing that happens is that you are a better parent now. He doesn't have to talk because you already know what he needs. Some children are 18 months old before they walk. My children that grew up to be good athletes did all the large motor skill activities earlier.
First children tend to progress more rapidly than second children. At your one year old well child check up ask the doctor to give you a chart with the age that children start doing each new developmental activity. That should help ease your worries. Enjoy your little ones!