TVGuide.com said Prospect Park, the production company that acquired the rights to the 41-year-old daytime drama, made the casting announcement Monday.
Mathison and Hartley will reprise their roles of Ryan Lavery and Dr. Cara Castillo Martin respectively, the report said.
The stars are the first to join the cast of the online edition of the soap, which moves online next season after wrapping up production Friday.
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