Just remember that not all yearling bucks are chased off by their mothers. Some doe social groups will contain adult does, their fawns from this year and a few fawns from last year which are now yearlings, both male and female. The yearling bucks will be lowest on the social ladder hence be religated to following at the "end of the line" as the group travels.

I don't know how many times I've heard hunters say they say a yearling buck "chasing" a whole group of does, when what they really witnessed was a doe social grouping running along with the lone male yearling bringing up the tail end of the line. The buck wasn't chasing, he was following the pack.