son of Hugh Jenks:
'William. Presumably ancestor of some London Jenks named as cousins in will of brother Richard. ... Administration on the estate of a William Jenks of Shrewsbury was granted in 1611 to the widow Alicia ...'
The "cousins" mentioned in his brother's will were Jonas Jenks, who is speculated to be William's son, and an unidentified William.
Note that on page 162, the author states "we cannot prove that William had children", and it is possible that the children assigned here (John and Jonas) were actually of the Jenks family of Clunbury.