This is entirely up to you, of course. But remember, once you reveal something you can’t take it back. It is wise to err on the side of revealing as little information as possible, and gradually add info until you’ve reached a level with which you’re comfortable.
Many people do not use their real names. Or they use their real names, but not the real names of their family members and co-workers. Certainly when dealing with children, it is prudent to use great caution. At the risk of sounding over-dramatic, there are some creeps out there. Even if you are writing a light-hearted, family-oriented blog, there is nothing to prevent someone with less-than-honorable intentions from stumbling upon what you’ve written. USE CAUTION.