(written from a Production point of view)
Ellen Ware Geer (born 29 August 1941; age 78) is the actress who played Doctor Kila Marr in the Star Trek: The Next Generation fifth season episode "Silicon Avatar". Geer filmed her scenes between Thursday 8 August 1991 and Thursday 15 August 1991 on Paramount Stage 8, 9, and 16.
She is the daughter of fellow TNG guest star Herta Ware, and the mother of Star Trek: Picard guest actress Willow Greer. Her costume was later worn by background actress Leslie McCasky in an episode of TNG and by Barbara Tarbuck in the Star Trek: Enterprise first season episode "Shadows of P'Jem" before it was sold off on the It's A Wrap! sale and auction on eBay. 
Geer has enjoyed a long, distinguished career in film and television. She began her career appearing as a nun in the 1968 Richard Lester drama Petulia. This film also marked the first credited appearance by future DS9 star Rene Auberjonois. Geer followed this with an appearance in 1969's The Reivers with her actor father, Will Geer.
In 1971, Geer played the deceased wife of the lead character in Kotch, appearing throughout the movie in flashbacks. (Biff Elliot also appeared in this film.) That same year, she became a regular on The Jimmy Stewart Show (which aired until the following year) and had a supporting role in the acclaimed comedy Harold and Maude (which was photographed by John A. Alonzo and featured costumes by William Ware Theiss). In 1974, she starred in two films which she also wrote: Silence and Memory of Us. Both featured her father.
The remainder of the 1970s consisted primarily of guest appearances and made-for-TV movies. TV shows on which she appeared during this time included Barnaby Jones (two episodes, including one where she played the wife of Gary Lockwood; both starred Lee Meriwether), Police Story (with Glenn Corbett), Charlie's Angels (with Louise Sorel), CHiPs (one episode with Marc Alaimo and later several episodes with Michael Dorn), and two episodes of Fantasy Island starring Ricardo Montalban (one episode also guest-starred John Fiedler). Her TV movie credits during this time included 1975's Babe (co-starring Byron Morrow and Meg Wyllie), 1976's The Lindbergh Kidnapping Case (co-starring Cliff DeYoung, Laurence Luckinbill, Phillip Richard Allen, Arthur Batanides, Peter Brocco, and Bill Quinn), and 1979's A Shining Season (with Ed Begley, Jr.). The only film on which she worked in the late 1970s was Jonathan Kaplan's 1979 film Over the Edge.
Films that followed included Kaplan's Heart Like a Wheel (1983, with Dick Miller), Something Wicked This Way Comes (1983), the 1985 science fiction comedy Creator (co-starring Virginia Madsen, David Ogden Stiers, Kenneth Tigar, Ian Wolfe, and Jeff Corey), Lonely Hearts (1991, with mother Herta Ware, as well as Bibi Besch, Joanna Cassidy, Miriam Flynn, and Charles Napier), the 1992 action thriller Patriot Games and its 1994 sequel Clear and Present Danger as Rose (the latter film also featuring Harris Yulin, Reg E. Cathey, and Vaughn Armstrong), Phenomenon (1996, with Brent Spiner and Richard Kiley), The Odd Couple II (1998, with Richard Riehle), and Criminal (2004). The remainder of her TV credits include guest appearances on The Waltons, Quincy, M.E. (with K Callan, Nicholas Coster, Jonathan Frakes, Robert Ito, Phillip Pine, and Garry Walberg), Dallas, The Practice, CSI, ER, NYPD Blue, and Cold Case (with Randy Oglesby). She also had recurring roles on Falcon Crest and Beauty and the Beast – the latter series starring Ron Perlman.
More recent credits include the recurring role of Lillian Sims in three episodes of Desperate Housewives (2007-2008, with Teri Hatcher, Brenda Strong, John Rosenfeld, J. Michael Flynn, Kevin Rahm, Ken Edling, and Arlo Hemphill), guest roles in Bones (2009, with Kelvin Yu, Matt Malloy, and Rick Scarry), The Mentalist (2009, with Jude Ciccolella), Medium (2010, with Bruce Gray and Jenette Goldstein), and Criminal Minds: Suspect Behavior (2011) as well as the drama Montana Amazon (2011, with James G. MacDonald).