A sister for Alexandra should be called....

[language]

Isabelle
Sophie
Estelle
Helena
Florence
Alice

or something else?

Marina

Sophie

Harriet
Madeline
Scarlet

:)

Zandra

My first thought was Isabelle; I also like Julia, Eleanor, Katherine, Elizabeth, Charlotte and Naomi.

Victoria, Katherine, Charlotte or Elizabeth- they are all quite traditional, long names but have the same nickname options as Alexandra