I'm not sure. I have tentatively separated two Thomas Chipman's of different lines
Thomas Chipman, of Whitchurch Canonicorum
Thomas Chipman, of Briantspuddle
There is referral to an original source document that may shed further light on the Chipman's & Darby's of Dorset. Be careful though about the term "cousin" - it's used more loosely than we define it today
From http://minerdescent.com/2011/12/19/john-chipman/
Thomas Chipman, his father, has inherited a valuable mill property as a yong man which had been administered and then taken over by his distant cousin Christopher Derby. Thomas had later married, but had never received any capital from Derby. John lived a few years during his youth with his uncle Christopher Derby who was prosperous at the time. He probably made provision for John to attend some sort of school where he learned to read and write. After Thomas’ death, his only son, John, at age seventeen emigrated to Plymouth in 1637 under indenture to Richard Derby, son of Christopher. When he was twenty-one, John Chipman made an effort to establish a claim against Christopher Derby, supported by testimony from Ann Hynd, a domestic from the Derby house, who had also come to Plymouth.
Marian Manson Chase do you have more clarification? I am bothered by the "1596" birth date of Thomas Chipman, of Whitchurch Canonicorum
That seems a bit young to be the father of John 'Elder' Chipman