Mollie ranks #830 with 141 female registrations. The name is a vintage spelling variant of Molly (itself a diminutive of Mary), and on a pet license it usually signals deliberate spelling preference: owners who picked Mollie over Molly are committing to the older form.
The spelling-as-statement choice
Mollie was the dominant American spelling in the late nineteenth and early twentieth centuries before Molly took over in mid-century. Households who choose Mollie now are usually doing one of three things: honoring a great-grandmother whose name was spelled this way, leaning into the Anglo-Irish vintage register on purpose, or matching a sibling-pet whose name carries the same antique flavor. See Molly for the modern-spelling cousin.
Sound and breed lean
Two syllables, front-stressed (MOL-lee), with a soft M opening and a gentle -y close. The shape calls warmly outdoors and pairs naturally with the affectionate household register. Mollie lands with notable concentration on Irish-coded breeds: wheaten terriers, Irish setters, and beagle mixes whose owners read the temperament through the warm name.
The counter-reading
The honest concern is that the spelling distinction is invisible in conversation. Most people will assume Molly when they hear it, and the vintage-statement only registers on the paperwork. If the household wants the older feel to show through, pairing with siblings who carry similar vintage spellings (Sadie, Maggie) helps. The human Mollie page shows the early-twentieth-century peak.