There is mention of an older Oswell Sill in New Hanover, NC Court Records from 1807 which I found looking for my Nathan WILLIAMS. It is copied below:
Friday, 21 August, 1807 (pp. 52 - 53 of Journal) "Edward St. GEORGE appointed guardian to John A., Edward, and Mary SILL, giving bond in 1000 lbs. with Wm. WILKINSON and NATH. WILLIAMS.
"John A. Sill bound apprentice to Benjamin JACOBS.Edward SILL bound apprentice to Thomas COWAN."
"Admn. Of the estate of N. SWANEY granted to John HARRISS giving bond in 300 lb. with Thomas COWAN and N. WILLIAMS."
"Thomas BISHOP, Alex McCULLOCH, Thos. HOWE, M. LEE, and Benjamin MOTT appointed to divide the real estate of Oswell SILL and the personal estate of Oswell and Priscilla SILL."
"The state vs. Timothy ROGERS, -Ed St. GEORGE, Anthony WILLIAMSON, Thos. Hunter, W. WILKINSON, Jonathan Stanley, James ALLEN, W. BETTS, Murdock MCKAY, Geo. NEWTON, H. WILLIAMS, Jno Larkins, Elijah SILL, and find the deft. Guilty.Ordered that he receive 39 lashes upon his bare back forthwith, that he remain in custody of the jailor till he gives security for his good behavior in the sum of 30 lbs. and security to keep the peace towards Thos. LEDDON in the sum of 30 lbs.
Source:Clarendon Courier, Volume 7, No.3, Fall 1995, p.53 Online: Clarendon Courier 1989-2006, Journal of the ONHGS, pub. 4X year