Pembrook McComas was the eldest son of early pioneers William Burke McComas and his wife Nancy D. (Heath) McComas who married in Cabell Co WV on 16 Feb 1832, and moved into early Platte County in 1840. They are buried in the McComas Cemetery, Platte Co. MO. Their son Pembrook married twice, first wife being Elizabeth Jane Kerr from Ohio (1830-1908) the daughter of James Kerr and Alice Elliott and 2nd wife Nancy 'Elizabeth' Clevenger from Illinois (1855-1935) whom he married 10 Oct 1904. She was the daughter of Job Clevenger and Mahala Elizabeth Sinclair. Nancy Elizabeth Clevenger was a widow, having first married Martin Dewey Follett.

The obituary for Pembrook McComas appeared in the Liberty Advance on 31 January 1927 and read:
Died at Age of 93
Pembrook McComas died at his home in Edgerton Thursday afternoon. Mr. McComas was 98 years of age, and had been very feeble and confined to the bed much of the time for the last two years. The funeral was held Saturday afternoon at 2 o'clock in the Methodist Church at Edgerton, and burial was at Mt. Zion Cemetery near there. The deceased was the father of Joe M. McComas of Liberty, and Mrs. Isaac Meismer (sic) of Cameron and Mrs. Nancy Newman of Britton, Okla., Norman Follett of Liberty, Miss Augusta Follett of Kansas City, and Mrs. Maynard Asher of Smithville are step-children. Mrs. McComas of the second marriage, survives. "Uncle Pem" as he was called by his many friends was a fine old gentleman and highly esteemed by all. he was born August 8 1833 in West Virginia and was the oldest of a family of eleven children. Only one is living now, Hiram McComas of Platte County. Mr. McComas was only seven years of age when his parents came to Missouri in 1840. He rode a horse most of the way, but the trip from St. Louis was made up the river by boat, leaving it at Liberty Landing. He remembered of coming through Liberty when it had few inhabitants in going to Platte County, which was his home all the rest of his life.