As Meredith puts Zola to bed and falls asleep, she begins to wonder -- what if her mother had never had Alzheimer's and she'd had loving, supportive parents? The reverberations of a happy Meredith Grey change the world of Seattle Grace as we know it. What if she had never met Derek in that bar and he had never separated from Addison? What if Callie and Owen had become a couple long before she met Arizona? And what if Bailey never evolved from the meek intern she once was?
Elenco: Ellen Pompeo , James Pickens Jr. , Chandra Wilson , Justin Chambers , Kevin McKidd , Jesse Williams , Patrick Dempsey , Sara Ramirez , Sandra Oh , Jessica Capshaw , Sarah Drew , Camilla Luddington , Caterina Scorsone , Giacomo Gianniotti , Kelly McCreary , Katherine Heigl , Chyler Leigh , Eric Dane , Kim Raver , T.R. Knight , Jerrika Hinton , Jason George , Isaiah Washington , Kate Walsh , Martin Henderson , Brooke Smith , Jake Borelli , Greg Germann , Chris Carmack , Tessa Ferrer , Gaius Charles , Anthony Hill , Richard Flood .