Actor / Actress Character Position Character Name Years of Appearance Alexander, Khandi Khandi Alexander Sister to Peter Benton Jackie Robbins 1995 -- 2001 Bartlett, Bonnie Bonnie Bartlett Mother of Mark Greene. Died early in Season 6. Ruth Greene 1997 -- 1998 Beach, Michael Michael Beach Husband of Jeanie Boulet. Contracted HIV, unwittingly passed it on to Jeanie, died offscreen of AIDS in 2008. Al Boulet (role played earlier by Bodison) 1995 -- 1997 Bodison, Wolfgang Wolfgang Bodison Husband of Jeanie Boulet Al Boulet (role later played by Beach) 1995 Bowen, Julie Julie Bowen Girlfriend of John Carter. In Season 5, Carter dated her but then contrived an excuse to break up with her. Roxanne Please 1998 -- 1999 Carson, Lisa Nicole Lisa Nicole Carson Girlfriend of Peter Benton. Claimed he was the father of her baby, later said he was n't (which was true) and tried to take Reese away from him but failed to. Later became erratic and vindictive before she died in an auto accident. Carla Reece 1996 -- 2001 Chinh, Kieu Kieu Chinh Mother of Jing - Mei Chen Lin Chen 2003 Cheung, George Kee George Kee Cheung Father of Jing - Mei Chen (later played by Henry O) Mr. Chen. Suffered permanently debilitating injuries in a car crash in China that killed his wife. Later euthanized by Jing - Mei. 2003 -- 2004 Cullum, John John Cullum Father of Mark Greene, a military veteran who finally reconciled with his son before dying late in Season 6. David Greene 1997 -- 2000 Culp, Steven Steven Culp Boyfriend of Elizabeth Corday Dave Spencer Davis, Oliver Oliver Davis Son of Samantha Taggart Alex Taggart (later played by Dominic Janes) 2003 -- 2005 Mornay, Rebecca De Rebecca De Mornay Carter 's cousin 's ex-wife Elaine Nichols 1999 Dillahunt, Garret Garret Dillahunt Ex-husband of Samantha Taggart (Earlier played by Cole Hauser) Steve Curtis 2005 -- 2006 Dooley, Paul Paul Dooley Father of Susan Lewis, proved to be a much better parent than his asshole wife. Henry Lewis 1995 -- 1996; 2004 Farentino, James James Farentino Father of Doug Ross Ray Ross. A charming man with issues not unlike the son he was never a father to. Died in a car accident in 1997. Field, Sally Sally Field Mother of Abby Lockhart Maggie Wyczenski 2000 -- 2006 Fisher, Frances Frances Fisher Mother of Kerry Weaver Helen Kingsley. A born - again Christian who gave Kerry up for adoption after giving birth as a teenager. Could not accept Kerry 's homosexuality, leading Kerry to not pursue any further contact with her. 2005 Freeman, Paul Paul Freeman Father of Elizabeth Corday Dr Charles Corday 1998, 2001 -- 2002 Glover, Danny Danny Glover Father of Greg Pratt Charlie Pratt. Greg 's long - lost father, who Greg located and tried to forgive for abandoning him, but ultimately could n't do so. 2005 Gregorio, Rose Rose Gregorio Mother of Carol Hathaway, who initially hated Doug and constantly undermined and fought with her daughter, but later was a good and loved parent. Helen Hathaway 1996 -- 1999 Gross, Michael Michael Gross Father of John Carter. Ineffectual man whom his son loved but did n't respect. John "Jack '' Carter Jr. 2001 -- 2004 Curtis - Hall, Vondie Vondie Curtis - Hall Husband of Carla Reece (Earlier played by Victor Williams) Roger McGrath 2001 Harris, Estelle Estelle Harris Mother of Jerry Markovic Mrs. Markovic 2006 Harnos, Christine Christine Harnos Mark Greene 's wife, then ex-wife Jennifer "Jenn '' Greene - Simon. Constantly bemoaned Mark 's low - paying, high stress ER career and his refusal to take lucrative jobs elsewhere. Eventually left him, filed for divorce, and married someone else. Not much of a mother to Rachel, disappeared for good after Mark died. 1994 -- 1996, 1996 -- 1998, 2001 -- 2002 Hauser, Cole Cole Hauser Ex-husband of Samantha Taggart Steve Curtis Hazlewood, Rebecca Jane Rebecca Jane Hazlewood Cousin of Neela Rasgotra Jaspreet 2008 Helgenberger, Marg Marg Helgenberger Doug Ross 's girlfriend & his father 's boss Karen Hines Hirsh, Hallee Hallee Hirsh Daughter of Mark Greene (Earlier played by Yvonne Zima) Rachel Greene 2001 -- 2002; 2004; 2009 Hudson, Ernie Ernie Hudson Father of Michael Gallant Colonel James Gallant 2006 Hurd, Michelle Michelle Hurd Girlfriend of Kerri Weaver Courtney Brown 2006 -- 2007 Janes, Dominic Dominic Janes Son of Samantha Taggart Alex Taggart 2005 -- 2009 Keach, Stacy Stacy Keach Father of Tony Gates Mike Gates 2007 Greenfield, Chloe Chloe Greenfield Daughter of Tony Gates Sarah Gates 2006 -- 2009 Kher, Anupam Anupam Kher Father of Neela Rasgotra Ajay Rasgotra Kher, Kiron Kiron Kher Mother of Neela Rasgotra Mrs. Rasgotra Kwan, Nancy Nancy Kwan Mother of Jing - Mei Chen Lin Chen 2000 Laurie, Piper Piper Laurie Mother of Doug Ross Sarah Ross 1995 -- 1996 Madigan, Amy Amy Madigan Mother of Samantha Taggart Mary Taggart 2009 Mayeux, Rosalee Rosalee Mayeux Mother of Ray Barnett Jacy Barnett 2007 McDonnell, Mary Mary McDonnell Mother of John Carter Eleanor Carter (née Ferguson) 2001 McFarlane, Andrew Andrew McFarlane Nephew of Peter Benton Jesse Robbins 2000 Morgan, Trevor Trevor Morgan Son of Donald Anspaugh Scott Anspaugh 1998 Newton, Thandie Thandie Newton Girlfriend and later wife of John Carter Makemba "Kem '' Likasu - Carter. Met John on a medical relief mission in the Congo. Fell in love with him and planned to be with him in Chicago, but their relationship never recovered after their son died in utero. 2003 -- 2005; 2009 Nozick, Bruce Bruce Nozick 2nd husband of Jennifer "Jenn '' Greene - Simon Craig Simon 1995 -- 1996 Parfitt, Judy Judy Parfitt Mother of Elizabeth Corday Isabelle Corday 2000 -- 2002 Parker, Andrea Andrea Parker Girlfriend of Doug Ross Linda Farrell 1994 -- 1995 Perrine, Valerie Valerie Perrine Mother of Susan Lewis Cookie Lewis. A selfish, self - centered woman who constantly enabled Chloe and disappointed Susan. 1995 Radanovich, Zoran Zoran Radanovich Brother of Luka Kovač Niko Kovač 2007 Ralph, Sheryl Lee Sheryl Lee Ralph Mother of Michael Gallant Gloria Gallant 2006 Richards, Beah Beah Richards Mother of Peter Benton Mae Benton 1994 -- 1995 Rhames, Ving Ving Rhames Brother - in - law to Peter Benton Walter Robbins 1994 -- 1996 Scarfe, Jonathan Jonathan Scarfe Cousin of John Carter Chase Carter. Spoiled rotten young man who fell into heroin addiction and was left nearly vegetative after an overdose, but was last shown having improved greatly and being able to function in a limited manner. 1997 -- 1998, 2001 Scott, Tom Everett Tom Everett Scott Brother of Abby Lockhart Eric Wyczenski 2002 -- 2003 Smith, Lois Lois Smith Grandmother of Samantha Taggart Gracie 2007 Sternhagen, Frances Frances Sternhagen Grandmother of John Carter Millicent "Gamma '' Carter 1997 -- 2003 Thedford, Marcello Marcello Thedford Brother of Greg Pratt Leon Pratt 2002 -- 2003 Valley, Mark Mark Valley Ex-husband of Abby Lockhart Richard Lockhart 2000 -- 2003 Victor, Renée Renée Victor Mother - in - law of Kerry Weaver Florina Lopez Walsh, Gwynyth Gwynyth Walsh Mother of Lucy Knight Barbara Knight 2000 Ward, Fred Fred Ward Father of Abby Lockhart Eddie Wyczenski 2006 -- 2007 Watkins, Matthew Matthew Watkins Son of Peter Benton Reese Benton 1999 -- 2001; 2009 Wilhoite, Kathleen Kathleen Wilhoite Sister of Susan Lewis Chloe Lewis 1994 -- 1996; 2002 Williams, Victor Victor Williams Husband of Carla Reece (Later played by Vondie Curtis - Hall) Roger McGrath 1998 -- 2001 Woodward, Shannon Shannon Woodward Sister of Samantha Taggart Kelly Taggart 2009 Zima, Yvonne Yvonne Zima Daughter of Mark Greene (Later played by Hallee Hirsh) Rachel Greene 1994 -- 2000 Actress uncredited Sister of Lucien Dubenko Victoria Dubenko 2006
who played dr green's daughter on er
Yvonne Zima Yvonne Zima Hallee Hirsh Hallee Hirsh