Thomas Manwaring & Ester Christopher did not have a son named David. Son,Thomas Manwaring & Lydia Waterhouse had a grandson, David, but his name would have been David Latham, son of Thomas' daughter Lydia and husband, John Latham married in 1778.
In my research in Lyme, Ct I could find no other David.
My list includes Oliver,son Richard, son Thomas, son Adam,son Adam, son Giles Manwaring.etc.
I hope you find David. I am interested to know about him.
OOPs! I goofed.
I have found a David Manwaring born in 1741, son of William Manwaring & Rebecca Gager. William is the son of Oliver Manwaring & Hannah Hough, grandson of Oliver Manwaring & Hannah Raymond. Could this be the David you are searching for?