Dinah Cox was born 27 April 1737. She was the daughter of John Cox and Mary Harlan. The family were of strict Quaker faith. Members of the Society of Friends wore plain clothes with no ornamentation or jewelry. They regarded all humans equal before God and addressed a person as "thou" so that they did not need to reference a person’s title.

When her grandfather Moses Harlan died in 1749 her brother Jacob received two hundred acres of land and was to pay each sister, which included Dinah, five pounds. Moses Harlan specified that his grand daughter Dinah Cox was to also receive his two year old bay mare. Dinah was twelve years old when she received the mare.

Dinah married Finley McGrew 30 June 1759. Finley had requested a certificate to marry from the Society of Friends and was a member of the Quaker faith. For whatever reason the two chose to marry in York Christ Lutheran Church in York County, Pennsylvania. Dinah, as was the custom, was soon visited by a committee and when she gave her acknowledgment was accepted back by her faith. Her husband Finley stated in the Menallen minutes:

                        "...whereas, I Finley...brought up and educated in way of blessed

                        truth...let out my mind as far as to be married by a priest and

                        to one of my own persuasion, although pre-cautioned to the contrary

                        by my friends...I am very sorry that I did not keep to the good order

                        amongst friends and I would be very glad that my friends would

                        find freedom and pass by and keep me under their care...I hope

                        through direct assistance to take better care."

They were accepted back into the care of the Society of Friends. Dinah and Finley had nine children. The children were raised under the auspice of Warrington Monthly Meeting in York County, Pennsylvania. Much of the province of Pennsylvania was largely of Quaker faith.

In 1779 Dinah her husband and children received a certificate from Warrington Monthly Meeting where they had continued since their marriage to join Hopewell Monthly Meeting. Their certificate was granted in 1783.

Hopewell Monthly meeting is located in Frederick County, Virginia five miles north of Winchester, Virginia. It is difficult to pinpoint exactly where the family was at this time for members of a given Monthly Meeting could live hundreds of miles from the meeting location. Many times committees were sent out to collect certificates and family information which could explain the delay of the certificate being granted.

In 1783 the family received a certificate from Hopewell to Menallen Monthly Meeting. Menallen was divided from Warrington as part of the growth process. It falls within the Warrington Quarterly Meeting in Menallen Township, Fayette County, Pennsylvania. Daughter Dinah apparently was spirited. When she was 16 years old the Monthly Minutes filed a complaint for her dancing. Quakers forbad music, dancing and cards.

In 1787 Dinah, husband Finley and her children Margaret and Jacob requested a certificate to Westland Monthly Meeting. It is doubtful they left prior to the marriage of daughter Rebecca, circa 1788 to James Mains. Westland was established by the Warrington and Fairfax Quarterly Meeting in 1785. The MM was located in Washington County, Pennsylvania and included Washington, Allegheny, Westmoreland, Fayette, and Greene Counties in Pennsylvania as well as adjoining counties in [West] Virginia and Ohio. Daughter Margaret had married William Wilson in 1792 and in 1793 the minutes show she was dismissed and had "married contrary to discipline." Margaret had married out of her faith and was dismissed from the Society of Friends.

Dinah’s husband Finley McGrew died 9 April 1812 and was buried in the Friends Cemetery, Sewickley, Westmoreland County, Pennsylvania. His burial was recorded in the Providence Monthly Minutes. Dinah died November 2, 1819 and was buried in the Friends Cemetery, Swickley, Westmoreland County, Pennsylvania.