I found a will of William Powell in Norfolk County written in 18 Jun 1690 and proved 17 Jun 1691. He mentions his wife Ann, father William and daughters Mary, Ann, Elizabeth, Sarah and Keziah. He says his wife is at the time pregnant.

And the will of John Powell dated 19 Dec 1687 proved 15 May 1688 mentions brother William Powell and cousins Richard and John Powell.

It’s possible that Elinor was William’s unborn child when he wrote his will in 1690 but he describes the plantation he now lives on as adjoining “my father Wiliam’s line”.