Little is known about her except that she shared her daughter's love of dolphins. When Russ was nineteen, and Temperance was fifteen, Christine and Max disappeared after going out to "run errands" (Christmas shopping). They encountered a hit-man from the criminal team they used to work with while they were shopping and they left to avoid people who would endanger themselves and their children.
Ruth died two years after she disappeared, due to skull trauma induced by foul play. She was killed by Vince McVicar with a spring loaded captive bolt stunner. Ruth survived for a year and a half after her encounter with McVicar as she was able to see the movie The Fugitive on April 22, 1993 at 9:00 in the Rialto Theater from a movie ticket that was recovered with her remains. She was buried on December 1993 at Sunset Memory Cemetery in Salisbury, Pennsylvania and her body was recovered in September 1998 by a grave digging crew. Zack mentioned that she was at the Jeffersonian for as long as Brennan since they both got there in 1998.
Ruth is only ever seen in flashbacks, a video tape given to Temperance by Max, and on the Angelator after Angela Montenegro did a computer image from Ruth's skull. Her granddaughter Christine Booth is named after her.
In Stargazer in a Puddle, Max gave Brennan a video tape that she left for her to watch on her 16th birthday. Ruth told her that Max would have wanted to keep their family together, but ultimately, she was the one who made the decision to leave her and Russ to keep them safe.
Christine Brennan/Ruth Keenan was also seen during a near-death experience when Dr. Brennan was shot by someone at the lab in The Shot in the Dark, during which she encourage her daughter to be more impulsive and emotional.