Prosper sits next to 3 phonetic neighbors — Jasper, Foster, and Chester are the closest matches by sound. Most share Prosper's French-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"to thrive, to succeed, prosperous"
"honoring God"
"brushwood town"
"knight, mounted warrior"
"little warrior, of Mars"
"remnants of a lake, driftwood"
"relating to Easter, Passover"
"man of the forest"
"gift of God, gift of Yahweh"
"round, barrel"
"son of William"
"star"
"Haelstein's settlement"
"servant of God"
"gentle ruler"
"son of William"
"vigorous youth"
"the kingdom of Ciar, County Kerry"
"archer, bow-wielder"
"the Lord is willing"
"God is with us"
Similar sound: These names share phonetic patterns with Prosper — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin origins, giving them the same cultural heritage as Prosper.
Rhythm: Prosper is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.