It may be possible to confirm family relationships by comparing test results with Gayle or other carriers of her ancestors' mitochondrial DNA.
Mitochondrial DNA test-takers in the direct maternal line:
Gayle (Schell) Foster:
Family Tree DNA mtDNA Test Full Sequence, haplogroup H1b, FTDNA kit #260996
It is likely that these autosomal DNA test-takers will share some percentage of DNA with Gayle: