Interestng enough: My Ackerman Family books from the David Ackerman Society states they are buried in Sleepy Hollow. I have a listing of the burials and they are listed in the following; Abraham Marlings- Rev. soldier. Wounded in the gallery fight off Tarrytown. On the same stone, Jennet, wife, daughter of David Ackerman and Maritie See-I see no actual burial for them in Sleepy Hollow. They are in the index and the reference is for this information.
The following is in the book; David,s/o Lodowyck bpt. Mar. 10, 1694 Hack Reform m. May 19, 1719 Maritie Zee bpt. April 1, 1702 dau. of Jacobus Sie and Catharine. David was a deacon in the Ref. Dutch Church at Phillipsburg(Tarrytown) Aug. 28, 1737 to Aug. 7, 1739 when he was dismissed. They probably moved to North Castle, NY. Both are buried in Sleepy Hollow Cemetery. Might want to contact the society and question this.I thought I had the complete listings but I could be wrong. This is also my family.