Answer by taking a quote from the following article:

Phillips was born Holly Michelle Gilliam in Long Beach, California, the second child of Joyce Leon (nee Poole), an accountant, and Gardner Burnett Gilliam, a merchant mariner. She has one older sister. Phillips's mother died of a brain aneurysm when Michelle was five years old. Between the ages of six and twelve, Phillips was raised in Mexico City, Mexico, where her father was studying sociology on the GI Bill at Mexico City College.

Phillips starred for six seasons on Knots Landing as the constantly scheming Anne Matheson Sumner, the mother of star Nicollette Sheridan's character Paige Matheson (a role which Phillips returned to for the TV movie Knots Landing: Back to the Cul-de-Sac (1997)). During this time, she also appeared in the films Let It Ride (1989); the thriller Scissors (1991), opposite Sharon Stone; and Joshua Tree (1993), starring Dolph Lundgren. In the mid-1990s, she played Abby Malone, mother of Valerie Malone (Tiffani-Amber Thiessen) in Fox's Beverly Hills, 90210.  In late 1987, Phillips sang backup vocals on Belinda Carlisle's number one hit, Heaven Is a Place on Earth, as well as on the Carlisle LP, Heaven on Earth. She had a guest role on the television series The Magnificent Seven, where she played Maude Standish, the mother of one of the Seven. Phillips' most recent serious acting job has been a recurring role on the WB drama 7th Heaven as Lily Jackson, sister of family matriarch Annie Jackson Camden (Catherine Hicks). She played Laura Collins in the television movie No One Would Tell (1996).  After the millennium, Phillips continued to occasionally appear in films. She had supporting roles in the comedies Jane White Is Sick & Twisted (2002); the drama Harry + Max (2004); and the independent comedy Unbeatable Harold (2006) In 2009, Phillips appeared at the annual TV Land Awards for the 30th year celebration of Knots Landing. She also appeared in a minor role in the Norwegian historical film Betrayal, which chronicles the German occupation of Norway.

Any other notable film works?
She had supporting roles in the comedies Jane White Is Sick & Twisted