Once the player character receives Yew's bear charm, the +10 Speech is an instant reward, similar to that of a bobblehead; it is not dependent on having the charm in the player character's inventory.
The player character will receive this reward only if the Speech check is passed or the Child at Heart perk used to find out what Harold is afraid of. Otherwise, Yew will not give the player character the charm. If Harold is burned, Yew will not give the charm either.
Sapling Yew claims she acquired her bear charm at age five.
Even though it looks exactly like a teddy bear when dropped, it looks like a bracelet with a bear figure hanging from it in the Pip-Boy image.
Though it no longer serves any purpose, this item is still found in the game files for Fallout: New Vegas.