Final answer:
In the 'Amulet' graphic novel series, Emily inherits her grandfather's magical stone, becoming a stonekeeper, and she learns to control her power.
Step-by-step explanation:
In the graphic novel series Amulet, the character who inherits her grandfather's magical stone and becomes a stonekeeper is Emily. Emily must learn to use and control her newfound power throughout the series, which is an essential element of the plot as she faces various challenges and adversaries. The story follows her journey of mastering the stone's abilities and the responsibilities that come with such power.