Marguerite Regina "Marg" (Mitchell) Muir, 76, passed away in Glendale, Arizona, on March 10, 2025. She was born in Baltimore, Maryland, on December 29, 1948, to the late John Samuel Mitchell Sr and Elizabeth Anna (Lang) Mitchell. She grew up in Parkville, Maryland, and she was a 1966 graduate of Parkville Senior High School. On June 2, 1967, she was wed to William Lambert "Bill" Muir III. After the loss of their infant daughter, Nicole Marie Muir, they decided on the path to adopt a child. Little did they know that the process would take them years due to many different hurdles, but they never gave up hope to adopt a child. Finally, on February 5, 1976, they were able to bring home a 7-month old baby boy, where they named him Mark Everette Muir.

Bill and Marg had no idea that their baby boy was born deaf, but once testing confirmed that, they made sure to learn sign language to communicate with their son. They also made sure Mark would go to school having teachers that did sign in sign language, and later on, sending Mark to Maryland School for the Deaf. In 1984, they even had a house built near Frederick, Maryland, so that they could be close to their son attending the Frederick campus. Marg, for the most part, was a homemaker, but loved her hobbies of gardening and looking for antiques. That led her to become an antique booth dealer for several years, enjoying the process of shopping, restoring, and selling antiques. Bill and Marg were churchgoers of Evangelical Lutheran Church in Frederick, Maryland, and they loved to travel — whether domestically in the United States or to countries such as Canada, England, France, Ireland, Scotland.

After living in Frederick for 22 years, in 2006, Bill and Marg decided to retire to Lancaster, Pennsylvania. It was the same year that Bill learned he had throat cancer and had surgery for it, losing his vocal cords in the process. It was fortunate that Bill and Marg were able to continue communicating with each other through sign language. The cancer came back in 2008 and Bill passed away. Marg continued to soldier on, continuing to live in Lancaster. In 2012, while unexpectedly going through a triple bypass heart surgery, she finally had the opportunity to meet her son Mark's biological mother, Audrey Rae Titus. Marg always wanted to thank Audrey for the chance to raise Mark, and Marg had that chance to do so.

By 2017, Marg's dementia began to affect her more and more so her son Mark had to bring her to Phoenix, Arizona, where he lived with his family. While in Phoenix, Marg was able to spend more time with her 3 grandchildren and 1 step-granddaughter.

Besides her parents, infant daughter, and her husband, she was predeceased by a brother, Joel Lewis Mitchell in 2015, and a half-brother, John Samuel "Jack" Mitchell, Jr. She is survived by her son, Mark Muir, and 3 grandchildren, Silas, Milo, and Gabby Muir, all of Wildomar, California; as well as a step-granddaughter, Harmony Hamilton, now of Maryland. Marg is also survived by her two nephews, John and Rev. Duane Mitchell, both of Maryland.

Per Marg's wishes, there will be be no services or viewing. Pending arrangements, it was her desire that she would be buried in Lancaster, Pennsylvania, where her husband's cremated ashes would be buried with her.