+---Richard Trethewy (ABT 1665-JAN 1741)
+---Richard Trethewy (ABT 1700-ABT 1764)
| +---Ann Martyn 
(ABT 1666-JUN 1738)
+---Richard Trethewy (ABT 1728-21 APR 1818)
| | +---Humphrey Harris
| | +---Gilbert Harris (ABT 1637-)
| | +---Gilbert Harris (ABT 1665-)
| | | | +---Richard Wills
| | | +---Jenifer Wills (ABT 1632-)
| | | +---Christian Best
| +---Jenifer Harris (ABT 1696-1780)
| | +---Thomas Hockin (-ABT 1607)
| | +---John Hockin
| | | +---Elizabeth ?
| | +---John Hockin
| | +---John Hockin (ABT 1616-DEC 1696)
| +---Elizabeth Hockin (ABT 1658-)
| +---Blanche ? (-ABT 1699)
+---John Trethewy (ABT 1762-29 OCT 1844)
| | +---David Warne
| | +---John Warne (ABT 1656-)
| | | | +---Henry Arthur
| | | | +---Gregory Arthur (ABT 1599-)
| | | +---Honor Arthur (ABT 1632-)
| | +---John Warne (ABT 1700-)
| | | | +---Richard Rounsevall
| | | | +---Gregory Rounsevall (ABT 1617-)
| | | | | +---Jane ?
| | | +---Jane Rounsevall (ABT 1664-)
| | | +---Mary Olver
| +---Mary Warne (ABT 1730-30 MAY 1786)
| | +---Johannes Doketon
| | +---John Doketon (BEF 1459-)
| | +---Thomas Doketon (BEF 1490-)
| | +---Richard Docton (-JAN 1571)
| | | +---Alicia Ash (BEF 1490-)
| | +---Thomas Docton (-AUG 1638)
| | | +---Thomasin Saunder
| | +---John Docton (ABT 1600-JUN 1650)
| | | +---Susanna (Susan) Babacom (-DEC 1634)
| | +---John Docton (ABT 1636-)
| | | | +---John Arundell of Lanherne
| | | | +---Thomas Arundell of Lanherne
| | | | | | +---Gerald Danet
| | | | | +---Elizabeth Danet
| | | | +---Thomas Arundell (-AFT 1620)
| | | | | +---Elizabeth Trengove of Nance
| | | +---Cecilia Arundell (-MAR 1639)
| | | +---Rachell Monp'son
| +---Honor Docton (ABT 1700-)
| | +---Thomas Tregeare
| | +---Henry Tregeare (ABT 1609-)
| +---Mary Tregeare (ABT 1655-)
| +---Mary ?
+---Richard Trethewey (ABT 1791-1871)
| | +---William Perkin (-1688)
| | +---John Parkin
| | | +---Mary ?
| | +---William Parkin (ABT 1690-)
| | +---William Parkin (ABT 1719-1784)
| | | | +---Richard Morlyn (-ABT 1730)
| | | +---Anne Morlyn (ABT 1695-)
| | | | +---Nicholas Trethewy (-ABT 1680)
| | | +---Julyan Trethewy (ABT 1652-)
| | | | +---Bartholomew James (-ABT AUG 1636)
| | | | | +---Sicelie ? (-1608)
| | | +---Petronell James (-ABT 1692)
| | | +---Joan ?
| +---Elizabeth Parkin (ABT 1766-24 MAY 1848)
| | +---Richard Osborne (-JUN 1667)
| | | +---Eme Varcoe
| | +---Richard Osborne
| | | +---Joan ?
| | +---Richard Osborne (-NOV 1707)
| | | | +---Arthur Michell (-ABT 1657)
| | | +---Constance Michell (ABT 1635-APR 1717)
| | | | +---Thomas Corne (-1647)
| | | +---Blanche Corne
| | +---Benjamin Osborne (ABT 1687-NOV 1738)
| | | +---Bettres ?
| +---Elizabeth Osborne (ABT 1721-)
| | +---Thomas Tregenza
| | +---Thomas Tregenza (ABT 1633-)
| | | +---Julian ? (-30 APR 1665)
| | +---Nicholas Tregenza (ABT 1655-APR 1734)
| | | +---Mary ?
| +---Ann Tregenza (ABT 1687-)
+---John Trethewey (31 DEC 1819-12 MAR 1898)
| +---Catherine Hicks (ABT 1793-1871)
| +---Elizabeth Binney
+---John Trethewy (07 MAY 1851-12 JUN 1939)
| | +---John Pinch (ABT 1515-)
| | +---Thomas Pinch (ABT 1540-)
| | +---John Pinch (ABT 1563-)
| | | +---Jone Hicks
| | +---Philip Pinch (ABT 1590-MAY 1675)
| | | +---Margaret West
| | +---Philip Pinch (ABT 1637-21 JUN 1725)
| | | +---Joanna ? (-OCT 1684)
| | +---George Pinch (ABT 1672-04 AUG 1742)
| | | +---Tamsin ? (-1726)
| | +---Philip Pinch (ABT 1700-)
| | | +---Margaret Betty (ABT 1673-)
| | +---George Pinch (ABT 1729-ABT 1781)
| | | +---Sussana Harris (ABT 1697-)
| | +---Philip Pinch (ABT 1769-MAR 1845)
| | | | +---James Trethewy (ABT 1517-ABT 1573)
| | | | +---Richard Trethewy (BEF 1550-)
| | | | +---Robert Trethewy (BEF 1575-DEC 1623)
| | | | | | +---William Hawkins
| | | | | +---Joan Hawkins (ABT 1530-)
| | | | +---Thomas Trethewy (ABT 1596-ABT 1664)
| | | | | +---Ann Burgess (-ABT 1637)
| | | | +---Robert Trethewy (AFT 1642-ABT 1690)
| | | | | | +---William Jolley
| | | | | +---Isabel Jolley (ABT 1606-)
| | | | +---Charles Trethewy (AFT 1673-DEC 1735)
| | | | | | +---John Scawen
| | | | | | +---Trehane Scawen (ABT 1614-)
| | | | | | | | +---John Trehane
| | | | | | | +---Elizabeth Trehane
| | | | | +---Dorothy Scawen (ABT 1653-)
| | | | | | +---Gregory Arundell (-ABT 1653)
| | | | | +---Dorothy Arundell
| | | | | +---Edith Crane (-ABT 1666)
| | | | +---John Trethewy (ABT 1700-)
| | | | | +---Jane Williams (BEF 1683-)
| | | +---Philadelphia Trethewy (ABT 1734-JUL 1796)
| | | | +---William Perkin (-1688)
| | | | +---John Parkin
| | | | | +---Mary ?
| | | +---Philadelphia Parkin (ABT 1694-MAY 1783)
| | +---George Pinch (ABT 1800-BEF 1871)
| | | | +---Andrew Elvans
| | | | +---Richard Elvans (ABT 1716-)
| | | | | +---Susanna Harris
| | | | +---John Elvans (ABT 1745-)
| | | | | | +---John Nankival
| | | | | +---Honour Nankival (ABT 1718-)
| | | +---Honour Elvans (ABT 1775-DEC 1841)
| | | +---Susan Varcoe
| +---Rebecca Arthur Pinch (ABT 1824-29 SEP 1865)
| | +---Phillip Arthur (ABT 1674-)
| | +---Edward Arthur (ABT 1704-)
| | | +---Joan Hicks (ABT 1676-)
| | +---John Arthur (ABT 1735-)
| | | | +---William Row
| | | +---Catherine Row (ABT 1714-)
| | | +---Catharine Mitchell
| | +---Richard Arthur (ABT 1769-JAN 1856)
| | | | +---John Yelland (ABT 1683-SEP 1714)
| | | | +---Richard Yelland (ABT 1714-)
| | | | | +---Elizabeth Chapman
| | | +---Mary Yelland (ABT 1741-JUN 1814)
| | | | +---John Thomas (ABT 1676-ABT 1745)
| | | +---Rebecca Thomas (ABT 1722-)
| | | | +---Nicholas Phillips (BEF 1664-)
| | | +---Mary Phillips (ABT 1684-)
| | | | +---John Mock (-OCT 1609)
| | | | +---Lancelot Mock (-FEB 1631)
| | | | | +---Joan ? (-OCT 1609)
| | | | +---John Mock (ABT 1601-ABT 1675)
| | | | | +---Joan Webber (-1623)
| | | | +---William Mock (ABT 1641-MAY 1719)
| | | | | | +---William Cock
| | | | | +---Julian Cock (ABT 1610-)
| | | +---Julian Mock (ABT 1663-)
| | | +---Dorcas ? (-AUG 1707)
| +---Rebecca Arthur (ABT 1800-JUN 1873)
| | +---William Lark
| | +---Edward Lark (ABT 1739-)
| | | | +---William Trudgian (-JUN 1720)
| | | +---Rebecca Trudgian (1692-)
| | | +---Ellinor Starke (-1726)
| +---Rebecca Lark (ABT 1773-)
| +---Honey ?
+---James Arthur Trethewy (05 MAR 1893-02 SEP 1955)
| +---Amanda Goodwin (05 AUG 1857-26 MAR 1940)
+---Gordon Maurice Trethewy (18 MAY 1920-15 AUG 1991)
| +---Alma Bernice Clark
+---Wyman (Bill) Maurice Trethewy (30 JAN 1942-)
| +---Wyma Jeanette Heintz
Maridee Susan Trethewy (04 AUG 1972-)
+---Norma Jean Nosack