Put it in the say_log instead

code/modules/mob/living/living_defines.dm

@@ -59,7 +59,6 @@
 	var/tesla_ignore = FALSE
 
 	var/list/say_log = list() //a log of what we've said, plain text, no spans or junk, essentially just each individual "message"
-	var/list/whisper_log = list() //a log of what we've whispered, plain text, no spans or junk, essentially just each individual "message"
 
 	var/list/recent_tastes = list()
 	var/blood_volume = 0 //how much blood the mob has

code/modules/mob/living/say.dm

@@ -357,7 +357,7 @@ proc/get_radio_key_from_channel(var/channel)
 
 	var/message = multilingual_to_message(message_pieces)
 
-	whisper_log += message
+	say_log += "whisper: [message]"
 	log_whisper(message, src)
 	var/message_range = 1
 	var/eavesdropping_range = 2