Jacaerys sits next to 4 phonetic neighbors — Viserys, Zacarias, and Jace are the closest matches by sound. Most share Jacaerys's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"royal dynastic heir (constructed language)"
"slender, narrow (from Irish Caolan)"
"son of Braxton"
"son of Lawrence"
"guardian of riches"
"God is gracious"
"powerful (by association with the watt unit)"
"landholder, lord"
"Western cowboy hat, frontier spirit"
"dwelling, honor"
"prosperous landowner"
"twin (loose association)"
"modern American creative formation"
"dweller by the dark meadow"
"descendant of little fawn"
"western settlement"
"salmon"
"from the Liffey valley"
"one who gives light"
"settlement on the River Ren"
"roe deer wood"
Similar sound: These names share phonetic patterns with Jacaerys — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have High Valyrian (fictional) origins, giving them the same cultural heritage as Jacaerys.
Rhythm: Jacaerys is a 4-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.