Complex sentence: Bracken makes a coin for Seth that he can communicate with him, while at Fablehaven, Grandma Sorenson wakes Kendra up and tells her Vanessa has revealed her secret.
Split into simpler sentences: Bracken makes a coin for Seth that he can communicate with him. At Fablehaven Grandma Sorenson wakes Kendra up and tells her Vanessa has revealed her secret.