diff --git a/src/daycare.c b/src/daycare.c
index 14053217d2..4199bfda67 100644
--- a/src/daycare.c
+++ b/src/daycare.c
@@ -23,7 +23,7 @@
 #include "constants/moves.h"
 #include "constants/region_map_sections.h"
 
-extern struct Evolution gEvolutionTable[][EVOS_PER_MON];
+extern const struct Evolution gEvolutionTable[][EVOS_PER_MON];
 
 // this file's functions
 static void ClearDaycareMonMail(struct DaycareMail *mail);