One of those pan-European nickname names much more familiar in Scandinavia and Eastern Europe than in the US, though related name Mina is making a comeback here.

Minna

Willa has become increasingly fashionable, with its combination of Willa (born Wilella) Cather-like pioneer strength and the graceful beauty of the willow tree. 
Sophie Turner and Joe Jonas are the latest celebrities to welcome a daughter named Willa. Other stars who used this name include actress Keri Russell, who named her daughter Willa Lou and the late actor Philip Seymour Hoffman, who used Willa for the youngest of his three children. David Mamet and Brian De Palma also have daughters named Willa, plus it's the middle name of Meryl Streep's actress daughter Mary (called Mamie.) Young Willa characters have appears on Six Feet Under and True Blood.
 Willa originated as a short form of Wilhelmina. After a half-century hiatus, it reentered the U.S. Top 1000 in 2010 and soared to the Top 500, for the first time since 1949, in 2015. Willa might also work as an honor name for an ancestral William.

Willa

omama's list "Uncommon Not Ostentatious Girls Names" of 2 great name ideas: Minna - Willa!

Uncommon Not Ostentatious Girls Names

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