Kicked off a baby? Are you sure your plant isn't grafted and the (I'm assuming it's a) basal sprout isn't from the root stock?

Obviously, trees in nature branch just fine w/o our help, so if you wait, the tree will develop secondary branching on its own. You CAN force it to branch by removing the terminal bud on the leader (or cutting back harder), which contains the apical meristem. This removes the source of the growth regulator/hormone (auxin) that suppresses secondary growth. IF you do that, you need to take steps to train one of the branches that emerge to the vertical as the new leader, or risk changing the trunk line from straight to something with a crook/bend/curves in it.

Al

Vase-like habit normal for this cultivar. Don't try to thwart its normal development. Eventually it may even be wider than you want, on its own.

Of course, if that one is a rootstock sprout, you want to snip it out completely.

LOL @ Kicked off a baby

Too funny.