When "Downton Abbey" returns for Season 3 in 2013 viewers will finally get to meet Lady Cora's (Elizabeth McGovern) mother, Martha Levinson, who is played by Oscar-winner Shirley MacLaine.The American Film Institute recently honored MacLaine with its 40th "AFI Lifetime Achievement Award" (Sun., 9 p.m. ET on TV Land), during which stars paid tribute to the veteran actress.