Agnes Capstick (also spelt as Capstack; 1570 – 1635) was the 13th great-grandmother of Cometan, classified as one of Cometan’s distant paternal ancestors in the McKerney family line. Agnes’ maiden name is unknown as are the identities of her parents. However, it is known that her husband was John Capstack (1570 – 1634) and that at least one of her sons was named Miles Capstacke (1595 – 1663). It is also known that Agnes died at the age of sixty-five in Dent, Yorkshire.
In Cometanic ancestry, Agnes is categorised as part of the 15th generation retrograde, classifying her as a distant ancestor of Cometan.