Kelly sits next to 4 phonetic neighbors — Kelley, Kell, and Kellan are the closest matches by sound. Most share Kelly's Irish-rooted cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"bright-headed warrior"
"rich friend"
"stubborn one"
"deep blue color"
"pierce the valley"
"royal power, bold ruler (via Kendrick)"
"helpful person"
"short form of Devon/Devlin"
"of God, heavenly"
"little fire"
"middle of the plain (city name)"
"God is salvation"
"dreamy obscurity"
"rye land; land where rye grows"
"hero, protector (fictional)"
"God is my father"
"rare, extraordinary"
"helmeted chief; armored head"
"little dark one"
"marshy land by a lake"
"badger settlement"
Similar sound: These names share phonetic patterns with Kelly — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old Irish origins, giving them the same cultural heritage as Kelly.
Rhythm: Kelly is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.