Sibling names for Sullivan
Names that sound like they belong in the same family as Sullivan usually share its era. These sister and brother names rose and fell on a similar curve to Sullivan, whose busiest decade was the 2010s, and are about as common, so neither child's name will feel dated or unusual next to the other.
Sister names for Sullivan
| Name | Meaning | Rank 2025 | Babies, last 5 years | Peak decade |
|---|---|---|---|---|
| Ellie | pet form of Eleanor, Elizabeth, etc. | #24 | 30,119 | 2010s |
| Delilah | #51 | 20,075 | 2010s | |
| Valentina | feminine of Valentinus | #35 | 21,268 | 2010s |
| Imogen | #1,117 | 974 | 2010s | |
| Dahlia | dahlia (the flower) | #215 | 6,123 | 2010s |
| Asiya | #1,211 | 788 | 2010s | |
| Liah | #1,322 | 843 | 2010s | |
| Gemma | gem, jewel | #170 | 8,040 | 2010s |
| Elyana | #1,176 | 766 | 2010s | |
| Myla | #210 | 7,616 | 2010s | |
| Amor | #1,668 | 690 | 2020s | |
| Evelynn | #301 | 4,992 | 2010s |
Brother names for Sullivan
Sullivan's era
Sullivan ranked #314 for boys in 2025, against #455 in 2015. Its best year was 2025, at #314. Names that rose and fell with it share its period feel, which keeps the set consistent.
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, Sullivan included.
Girls: Elizabeth, Maria, Lydia, Cecilia, Julia, Miriam. Boys: Anthony, Wesley, Vincent, Calvin, Victor, Oscar.
Same era, but close to Sullivan
These names follow Sullivan's curve too, but we left them out above because they share a first letter or an ending with Sullivan. 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 Sullivan's since 1880, and its recent number of babies is within about twelve times Sullivan's, so the names are in the same league. Names starting with the same letter as Sullivan or with the same ending are left out, so the names go together without matching. Spellings of Sullivan itself are excluded.