Oh man I feel like that’s a specific joke on a historical drama I’ve run across.
TL — yeah it’s an old grammar thing, o-xyz お等 is a female name convention basically until the Showa era.
Edit: well damn it’s almost certainly this. One of the thousand historical comics you find in school libraries
シーボルトお稲: 日本で初めての女性西洋医 (マンガ大江戸パワフル人物伝)