Per Massachusetts, Town and Vital Records, 1620-1988, Samuel is the son of Joshua Lamb and Mary.
Name: Samuel Lamb
Event Type: Birth
Birth Date: 9 Apr 1686
Birth Place: Roxbury, Massachusetts
Father Name: Joshua
Mother Name: Mary
Mary is documented as Mary Alcock in The Chandler family, the descendants of William and Annis Chandler who settled in Roxbury, Massachusetts.
Erica Howton, it looks like you changed this. Do you have a source for your change?