FRANCIS, John and Dorothy Coffin of Newbury, Apr. 22, 1731, in Newbury.
↑Source:Medford Historical Register, Vol. 8, p. 38 add a third child named Mary. Presumably they misread the birth record as Polly instead of Dolly, an error that exactly happened here, so not unknown. This source apparently adds Dolly based on the probate without realizing it was the same person as the birth record that they read as Polly.