There are three brothers total in the band. Kevin, the oldest, Joe, the middle child, and Nick the youngest. Although some maybe mistaken, Nick is not the youngest in the family. There is also another Jonas brother named Frankie. Who is considered to be the ''bonus Jonas'. The older brothers will grow up with much publicity where Frankie was on Hannah Montana for a few episodes I do believe.
Now my complete opinion on the Jonas Brothers is that they are OK but the are way to young to be in the music business. I bet some of their voices haven't even changed yet. I don't mind some of their songs I do have to say but still out of three Jonas' I give them a 1/3 + 1 bonus Jonas;)