Last April’s departure of former Disney (DIS) COO Tom Staggs, a long-time exec widely speculated to be the next in line to current CEO Bob Iger, left the company without a clear heir apparent—at least not an internal one.

Assuming Iger doesn’t extend his current contract, which expires in 2018, the company will need to name a successor sooner rather than later, and that doesn’t give them much time to groom someone from the inside. That’s why rumors that the top job could go to someone like Facebook (FB) COO Sheryl Sandberg—a Disney board member—are starting to look a lot more believable.

For more on Bob Iger, watch this Fortune video:

Whoever does become the next CEO of Disney, they’ll have some big shoes to fill. Under Iger, the Mouse House has made some massive bets, most of which have paid off (the acquisitions of Pixar, Lucasfilm, and Marvel, to name a few). But times are a little less joyful at Disney these days, as the company tries to get ahead of the latest major shifts in the media landscape. Bringing in someone with digital experience makes even more sense in light of those challenges.