Based on approximate age, surname and location in Hartford, I am surmising that Ruth Peck may be the daughter of John Peck (b.1655). It is of course also possible that she had married a Peck prior to marrying Sedgwick, perhaps even Joseph (b.1681). For now, I’ll guess that she is a sister of Joseph and Rachel who was not listed on the handwritten chart for Pecks (although there is open space that looks like it was meant for at least one more name). Some look at Hartford cemetery records would turn up more information, I’m sure.