Rebooting without doing endcli won't cause this. If you really want to kill it, open up a shell and type:
status
then press return. This will show all of the running processes. Then type
break processnumber
where processnumber is the number of the process you want to break (obviously

)
However, it may just be the case that something in your startup-sequence or user-startup have used the Run command to detach to their own shell, which IIRC will cause subsequent shells to have a different number (since they're numbered consecutively).
Edit - Opus beat me to it

Also, to give an example of how normal this is, my 3.1 installation inside UAE has quite a few patches loading on boot, and opening up a shell starts process 10. So I really wouldn't worry about it.