Brothers & Sisters Sneak Peek: "Almost Normal"

Kitty Walker has cancer.

The Brothers & Sisters character was diagnosed with Lymphoma last week, but only her mother is aware of the disease as we head into Sunday's all-new episode, "Almost Normal."

That may change by the time the episode concludes, but the cancer is still a mystery when Kitty joins Rebecca for some wedding dress shopping early in the hour.

Viewers know why Kitty is acting so sentimental, but in the clip below, Rebecca has no idea.