We aren't the only ones still mourning Matthew's untimely demise. When Downton Abbey returns for a fourth season, Lady Mary (Michelle Dockery) will still be grieving the loss of her husband six months earlier. ITV has released the first photo of the heartbroken mother and her new baby George from the upcoming season.The Associated Press reports that Shirley MacLaine will reprise her role as Cora's brash American mother. Downton has also recruited Welsh actor Tom Cullen to step in as Mary's new love interest Lord Gillingham, a family friend of the Crawleys who has known Lady Mary since childhood.Cullen is only one of many new characters Downton is adding. Dame Harriet Walter will play Lady Shackleton, an old friend of the Dowager Countess. Nigel Harman will portray a visiting valet Green. Julian Ovenden will play aristocrat Charles Blake, and Joanna David will appear as the Duchess of Yeovil."The addition of these characters can only mean more delicious drama, which is what Downton Abbey is all about," said Masterpiece executive producer Rebecca Eaton.How do you feel about Downton trying to replace Matthew so soon?