You and I have apparently came to the same conclusions. I have a copy of the Book "Van Der Slice and Allied Families" compiled by Howard Vanderslice and Howard Norman Monnett,Copyright 1931 by Samuel I Vanderslice of Los Angeles, California and printed by Neuner Corporation of Los Angeles. On pages 35 and 36 is the family of Daniel Vanderslice (Henry, Anthone, Reynier) who was born February 17, 1759 in Providence Twp., Montgomery County Pa. and died in Philadelphia, December 30, 1812. He married Margaret Clemmons who was born ca. 1780 and died January 13, 1815. The book list their children as:
Daniel Vanderslice, Jr. born Feb 10, 1779 [ this must be a mistake if Daniel Vanderslice was a son of Margaret (Clemmons Vanderslice as Daniel Jr. was born before Margaret according to the book.
The next child shown in the book is Thomas Jefferson Vanderslice. The book does not show when he was born or anything else about him. The Thomas Jefferson Vanderslice who was a river pilot at the mouth of the Mississippi in 1850 and 1860 was born about 1801 according to the censuses. The censuses and obituaries in New Orleans shows that Thomas Jefferson Vanderslice was married to an Elizabeth unknown. She may have been a second wife. They had four known children: Daniel T. Vanderslice born 1842, died 20 January 1865 at Mobile, Ala,; Catherine Vanderslice, born January 1845, died August 19, 1845 at The Balize, Plaquemine Parish Louisiana; Cass Vanderslice, born ca. 1848; Blanch Vanderslice, born ca. 1850, died Nov. 4, 1861. At the same time that T.J.V was enumerated in Plaquemine Parish La. there was another Thomas Vanderslice in the same area who was born in Kentucky ca. 1828. This may have been a son of TJV by a prior, unknown wife or he may have been some other close relative of TJV. The Obituaries in the New Orleans newspapers for TJV's children also request Kentucky Newspapers to carry the obituaries. This would indicate to me that TJV still had relatives in Kentucky in the mid 1800s.
I have not found a connection but I had a Benjamin Vanderslice in my line who was born in Pa. about 1765. He married Margaret Scott in Mercer County Kentucky March 12, 1795. Their first child was named Thomas J. Vanderslice, born Feb. 14, 1796 in Kentucky. The family moved to Christian County Kentucky where Thomas married Margaret Smith on Nov. 16, 1816. Benjamin and Thomas moved to Alabama about 1820.
Back to the children of Daniel and Margaret Vanderslice, according to the book, the next child was Catherine Vanderslice who was first married to John A. Roke and second to an unknown Synder.
The next child was John Henri Vanderslice who was born in Philadelphia, Pa. March 4, 1802.
I do not know what became of the Thomas Jefferson Vanderslice who was the river pilot after 1865. I do not know on which side of the War he supported. Perhaps he was killed during the War.