lazyraider - can set a target to follow. When I used to do this it had a problem in BGs where, if it died it would try to use a flying mount to get back to you... I got around this by using an old version which was only able to use ground mounts but I haven't done this in months so it might be updated/changed now and work in BGs.
You will also need an addon (from curse) that automatically releases your bot if it dies, can't remember the name but a quick search on google will work.
log your bot account, invite the char in with your main account (a lot of UIs/addons can use an "autoaccept invites from friends/guild") and once in a party start the bot with the botbase lazyraider. config lazyraider so your main char is set as the tank and you have the "follow tank" option ticked. Set a distance to follow, 5-10yards is good as the bot may not move in combat anyway. Lazyraider's possibly a bit buggy at the moment, a friend of mine says it works best when you start it in the BG rather than before you join.
you need to manually accept the queue on the bot account and will need to manually release if you die unless you have the wow addon from curse or a little plugin that someone made for me once on here called "release me"... again, a search will likely bring it up.
