A special edition of "20/20" will air tonight on ABC at 10pmET.

The hour will be a Barbara Walters special called "Farrah's Journey." Sources close Farrah Fawcett tell Walters these could be her final hours.

Fawcett's 2-and-a-half year battle with cancer was documented in an NBC News special last month.

This morning on GMA, Walters said, "I'm not sure if she's going to make it through the day. She's had her last rites."

> Update: At 12:51pmET, the cable news networks are reporting Farrah Fawcett has died.