This green to Lvl32 cub bear agros to all bears attacked close by, not just Mom.
If you hit him at any point, no matter how far Mom is, she comes running as well.
If he agros, then I would feign death, or zone. OR you could take mom too if you have the MP/HP left to try it.
I get them kiting a bit, but then, its near the zone entry, and easy to clear that way if you can FD.
These three bears are great ways to get HQBear for skilling while over Lvl 25, so you don't just go running around noob starting areas blasting the Level 9-12 bears. I have had 2 HQBears drop at once, also.