Yes, I've come across the Abercrombys of Tullibody and Skeith as well. I wonder, in fact, if there may not have been two only distantly related families who held the same lands in succession (with the George who died in 1699 being the last member of one), which would complicate this line even further. I've been trying to develop a pedigree of the family from contemporary records, but have yet to find anything that would provide evidence of a link with John Joseph Abercromby:
Adam Abercrombie was retoured heir to his father William Abecrombie of Overskeith in the lands of Ovir and Nethir Pitglasseis within the bishopric of Aberdeen, the lands of Auchnahandauche adjacent to the previous, the lands of Overskeith in the barony of Deskfurde, and two parts of the lands of Enoch in the barony of Coronassie, 31 October 1606 (Inq. Ret., Banff, no. 24).
George Abercromby, apparent of Skeith, was one of "heretors and gentrie of Banffshyr" who appeared for the appointing of a guard and the revaluation of the shire, 2 December 1653 (Banff Records, 143).
George Abercromby of Skeith witnessed the baptism of Thomas Muirsone in Deskford, 30 June 1677 (OPR, i. 25). He was described as "Laird of Tilliboddie and Skeith" when he witnessed the baptism of George, son of Alexander Abercromby in Deskford on 21 August 1686 (OPRs, i. 38). He held Skeith, situated in Deskford parish and valued at £180, at the time of the 1690 valuation roll (Banff Records, 271).
Alexander Abercromby of Skeith was "of Berrihillock" as early as 1691 and "of Skeith" by 1699. He was named a Commissioner of Supply for Banffshire, 19 June 1702 (Banff Records, 232) and again in 1704 (Banff Records, 258) and was appointed a Justice of the Peace for Banffshire, 4 June 1706 (Banff Records, 281). He was still, or was again, a Commissioner of Supply, 7 March 1716 (Banff Records, 316). He sold his estate to the Earl of Findlater in 1721 (Cramond, Annals of Cullen, 66). He married Marrat Abercromby, who was described as the "Good wife of Berrihillock" when she witnessed the baptism of Marrat Wilsone in Deskford, 2 August 1696 (OPRs, i. 50a).
i. George, of whom below.
ii. Francis, baptised 10 September 1691 in Deskford; witnesses not given (OPRs, i. 42a).
iii. Mary, baptised 14 June 1693 in Deskford; Mr. James Hendersone, Minr., Walter Ogilvy of Airdoch, Mary Gordone, Lady of Birkenbogg, and Mary Hendersone, good wife of Airdoch, witnesses (OPRs, i. 45a).
iv. child, baptised 22 June 1694 in Deskford; witnesses not given (OPRs, i. 47a).
v. Elizabeth, baptised 5 May 1696 in Deskford; witnesses not given (OPRs, i. 49).
vi. James, baptised 12 March 1698 in Deskford; John Gordon of Letterfury elder, John Innes in Nealtry, and John Ogilvy witnesses (OPRs, i. 51).
vii. Grissell, baptised 3 August 1699 in Deskford; witnesses not given (OPRs, i. 52). She witnessed the baptism of Grissell, daughter of William Abercromby in Skeith, 8 October 1715 (Deskford OPRs, i. 66).
viii. Mary, baptised 25 July 1700 in Deskford; James Ord, Walter Ogilvy, Mary Hendersone, and Mary Follae witnesses (OPRs, i. 53a).
ix. Walter, baptised 26 August 1701 in Deskford; Walter Ogilvy of Airdoch and Walter Ogilvy in Blearock witnesses (OPRs, i. 54).
George Abercromby, younger of Skeith, was baptised 21 August 1686 in Deskford; George Abercromby of Tullibody and Skeith witness (OPR, i. 38). He was one of Banff heritors involved the 1715 rebellion according to a letter from Lord Chief Justice Cockburn to Lord Townshend, 8 September 1716 (Banff Records, 322). By Margaret Pack he had an illegitimate son,
James, baptised 6 November 1712 in Deskford; James Stronnach, James Dow, James Steinsone, James Sinkler, Elspet Jonston, and Helen Steinsone witnesses (OPRs, i. 64a).
By Marrat Machatty he had another illegitimate son,
William, baptised 13 February 1715 in Deskford; no witnesses given (OPRs, i. 66a).
All the best,
Kelsey