Samuel Foster, s/o Dea. John and Hannah (Stetson) Foster, d. 2 Aug 1778, aged 78 y., 8 mo., and 4 d. [This would put his birthday in late 1699 which would suggest he is a twin with John?] Married (1) Scituate 10 Oct 1723 Margaret Tilden, m. (2) Kingston 29 Nov 1750 Margaret (Marshall) Wadswroth.
Foster, Samuel, h. Margarit, [died] Aug. 2, 1778. [a. 78 y. 8 m. 4 d., G.R.1] [GR1=Old Burying Ground back of the First Church]
↑ Samuel's birth is not listed in the family in Source:Mayflower Descendant, p. 2:20, "Family of John ffoster and hannah his Wife", but is called his eldest son in John Foster's will. Assuming son John died young, since he is not named in the will, Samuel could have been born after John in 1699, and still qualified as oldest son at the time the will was written, but clearly was born before Thomas in 1705. It would be a very tight fit to squeeze in Samuel sometime between his parents' marriage and John's birth, so it does not seem that he would have been born before John.