Family member allowed to be in the cab?

Depends on your company if they have a rider program some do some dont and most that do have age restrictions

 

Most companies will allow family one at a time. But it's usually they have to be 12 yrs old. It depends on their insurance carrier. Usually you have to sign a waiver ahead of time showing permission.
Then again I have seen whole families in a truck.

 

Over the summer I have seen *a lot* of dads out there hauling their kids. Only 11.5 years and I can take my son lol.

 

Bare in mind with young children, the "coolness" of riding in the big truck wears off quickly, stock up on their fave. dvd's and if they get tired of sitting shot-gun, slip'em off to the bunk to watch a movie. I heard that most now the youngest allowed is 10 years, some companies only have Spouse riders, some have immediate family, while others also allow Pets (for a cleaning deposit). Check with the company, or your insurance agent if you operate your own authority.