Dinah Luttrell (unknown) - Why doesn't the will show all children?

Michael Luttrell, Sr.
Joseph Luttrell

She is different from Dinah Luttrell

The About for Dinah Luttrell mentons 12 children:
In his last Will, Michael left items of personal property to each of his children:

[Mrs.] Franklin McKinzey,
Hannah Luttrell,
Abner Luttrell,
Lydia Luttrell,
Michael Luttrell,
Nathan Luttrell,
Dinah Luttrell,
Richard Luttrell,
Sarah Luttrell,
Dolly Luttrell, and
Betsy Luttrell.
To his son Lott Luttrell

James Earl Sosh your mother is a Luttrell?

Yes my mother is a
luttrell. My grandfather was Forrest Luttrell married to Helen K Luttrell.

A source gave me the following information for Samuel Luttrell, who he claims is the father of Joseph.

Samuel Litteral 1730 Stafford, Stafford, Virginia, United States Died MAR 16, 1778 Fauquier, Virginia, United States
his wife Dinah Shumate 1739 Fauquier, Virginia, United States Died MAR 16 1788 Fauquier, Virginia, United States

Her Parents John de la Chaumate AUG 1, 1707 Stafford, Virginia Died MAY 19, 1783 Elk Run, Fauquier, VA, USA
Married 1728 Stafford, Stafford, Virginia, United States
his wife Judith Bailey MAY 1708 Stafford, Stafford, Virginia, United States Died OC 25, 1784 Fauquier County, Virginia, USA