And even beyond the wide range of normal development, there are always those early bloomers and late bloomers who are also developing normally, too.
If your child isn't reaching his developmental milestones on time though, it would be good to talk to your pediatrician to see if there might be a problem with his development and any kind of developmental delay.
Take that group of 12 month olds again. If you notice that they are all either cruising or walking, but your child still isn't even pulling up to a standing position, then he likely is delayed. Talking to your pediatrician would be a good next step in evaluating his development.

