Sibling names for Millie
Names that sound like they belong in the same family as Millie usually share its era. These sister and brother names rose and fell on a similar curve to Millie, whose busiest decade was the 2020s, and are about as common, so neither child's name will feel dated or unusual next to the other.
Sister names for Millie
| Name | Meaning | Rank 2025 | Babies, last 5 years | Peak decade |
|---|---|---|---|---|
| Ophelia | help (Greek, via an Italian coinage) | #264 | 5,766 | 2020s |
| Nora | short form of Eleanor or Honora | #20 | 30,984 | 2010s |
| Lucy | light (Latin root) | #25 | 25,390 | 2010s |
| Adelaide | noble kind | #289 | 5,643 | 2010s |
| Eliza | my God is an oath (short form of Elizabeth) | #115 | 11,878 | 2010s |
| Stella | star | #52 | 22,450 | 2010s |
| Aurelia | golden (probable) | #290 | 4,062 | 2020s |
| Clementine | merciful (feminine of Clement) | #456 | 2,985 | 2020s |
| Emmy | pet form of Emma, Emily or Amelia | #445 | 3,181 | 2010s |
Brother names for Millie
| Name | Meaning | Rank 2025 | Babies, last 5 years | Peak decade |
|---|---|---|---|---|
| August | venerable, majestic | #81 | 17,891 | 2020s |
| Enoch | #746 | 1,707 | 2010s | |
| Fletcher | arrow maker (English surname) | #547 | 2,334 | 2010s |
| Royal | royal; or from English place names | #476 | 3,948 | 2010s |
| Ambrose | immortal, divine (Greek) | #735 | 1,794 | 2020s |
| Watson | son of Wat (Walter) | #1,011 | 1,631 | 2020s |
| Asa | #483 | 3,143 | 2010s | |
| Jasper | treasurer (Persian) | #129 | 14,304 | 2010s |
| Lucian | of Lucius (light) | #462 | 2,930 | 2010s |
| Ellis | from Elis, a medieval form of Elijah | #243 | 6,029 | 2010s |
| Cyrus | #268 | 5,775 | 2020s | |
| Cal | #543 | 1,942 | 2020s |
Millie's era
Millie ranked #73 for girls in 2025, against #469 in 2015. Its best year was 2025, at #73. A sibling name from the same wave will sound like it was chosen by the same parents; a name from an older or newer wave can make one child's name feel dated next to the other's.
Timeless names that go with any sibling
These names have been used steadily for a hundred years, so they sit comfortably next to a name from any era, Millie included.
Girls: Elizabeth, Lydia, Cecilia, Julia, Nina, Carmen. Boys: Samuel, Anthony, Wesley, Vincent, Calvin, Victor.
Same era, but close to Millie
These names follow Millie's curve too, but we left them out above because they share a first letter or an ending with Millie. Some parents like that echo; if you do, start here.
How these were chosen
Each suggestion's share of US babies has followed a curve close to Millie's since 1880, and its recent number of babies is within about twelve times Millie's, so the names are in the same league. Names starting with the same letter as Millie or with the same ending are left out, so the names go together without matching. Spellings of Millie itself are excluded.