Lillie

Lillie was more popular than Lily in the 19th century and 20th century USA. Probably because it was used more often as a diminutive of Elizabeth/Lillian in the olden days!
By the 80s in the USA, Lily grew in popularity.
https://www.behindthename.com/name/lillie/top/united-states?compare=lily&type=rank

Nickname for Elizabeth, Elisabeth, Lilianne, Lizianne, Lizabeth, Eliza, Lisabeth, Elisabethanie, Elizabethany, etc. Variants: Lily, Lilli, Lilly, Lili, Lilley.

In 2018, 83 is the most common age for an American (U.S.) Lillie who is registered female with the Social Security Administration. It is the 671st most common female first name for living U.S. citizens.