Mrs. Smyth and her husband were the ones who began creating the Infinity Ring, although Sera was the one who finished it. In A Mutiny in Time, while testing out the Ring, Mrs. Smyth, along with her husband, were left in time without a time travel device. They spent the majority of the series traveling to wherever a Great Break is, occasionally being able to contact Dak. In The Iron Empire, Mrs. Smyth and her husband reunite with their son.
A Mutiny in Time
Mrs. Smyt first appears in the funeral of Dak's uncle, and tries to make him keep quiet, but he blurts out facts anyway.
Her more improtant appearance is in after Sera has figured out The Missing Piece. She is agitated and suspicious, since she fears the SQ might now about the time machine. She, Mr. Smyth, Dak and Sera head to the lab in the barn. They finish last details (such as a DNA recognition lock) and order Dak and Sera to stay, since she and her husband will do a trial run. Dak springs with them (bringing Sera) and travels to the American Revolution. They are forced to be silent, since Redcoats seemed to be around. After they are discovered, Mr. and Mrs. Smyth distract the redcoats, and Dak and Sera return to the present. Sera explains that Dak's parents have become anomalies and travel through time sporadically.