It may be possible to confirm family relationships by comparing test results with Andrea or other carriers of her ancestors' mitochondrial DNA.
Mitochondrial DNA test-takers in the direct maternal line:
Mitochondrial DNA Test Full Sequence, haplogroup H1C3
It is likely that these autosomal DNA test-takers will share some percentage of DNA with Andrea:
AncestryDNA, GEDmatch A554972[compare], Ancestry member andrea_zuercher