Check for cemetery records with the church, sexton and/or funeral directors. Visit the cemetery and take a picture of the tombstone. Check the obituaries in that time frame.
Know your relationships: An ancestor is a person from whom you are descended. A descendant is a person who is descended from an ancestor. A relative is someone with whom you share a common ancestor but who is not in your direct line.
In Colonial days, men were eligible for service at age 16. Some lied about their age an entered before age 16.
Information in this source seems to address the research question all by itself.evidence speaks to the point in question.
[Sources & Evidence]
There are three types of wills: Attested, Holographic and Nuncupative. The attested will is the most common and is prepared for the testator. A holographic will is written by the testator himself. A nuncupative will is the deathbed wishes of the testator, recorded by a witness present at the bedside. All wills must be witnessed.