I'm a descendant of William Pool Jr through his son Samuel. My information shows William Pool Jr was born in Johnston County, NC, in 1720, and died there in 1763. He married Sarah Scott and according to his will had six children; John, Samuel, Steven, Sarah, Penelapy, Winifred).
During the same timeframe I see other listings in the area for families named "Poole" and I believe at some earlier point they are connected.
I have been unable so far to find information on the parents of William Pool Jr. The fact that "Jr" accompanies his name of course leads me to assume his father's name was William, but that is a common enough name to occur multiple times in NC and VA even in the 1700's.
If you have any information to share I'd love to hear from you!