Which messenger of the Philippians fell ill and nearly died, according to Philippians 2?

Answer: Epaphroditus

Epaphroditus, the Philippians' messenger to Paul, was sick nearly to death, but God had mercy on him.

“But I thought it necessary to send back to you Epaphroditus, my brother, fellow worker, and fellow soldier, who is also your messenger and minister to my needs.”— Philippians 2:25 (BSB)