It might not be the name many Grey's Anatomy fans were hoping for, but it will have to suffice for now:

Kate Burton, who recurred for years as Meredith's mother, Ellis, will return to this ABC hit in February for a special Sweeps episode that takes place in an alternative reality. The installment will give fans a look at how Meredith's life would have been different if her mom never suffered from Alzheimer's.

Kate Walsh is also booked for the episode (which will be titled "If/Then"), as it examines Derek's universe had he never split with Addison.

Many readers have been expressing their desire for either Katherine Heigl or Isaiah Washington to appear again, but there's no reason at the moment to expect either actor will show up. We'll be the first to tell you if that changes.

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.