George Weasley
Sometime in the middle of the night between Sunday and Monday, George will be woken by a vivid and violent dream about Percy telling him that Fred died. In the dream, he will get as far as seeing his twin's stuffed in an alcove before he's jarred awake. He will be at Lydia's and go into a full on panic, needing to get home and check on his brother, who is, in fact, quite alive and very annoyed at being jumped on at such an unholy hour.
He will be so freaked out that he won't immediately notice that he has gone totally deaf in his left ear, which will persist a while before slowly returning to normal.
The rest of George's other life will come to him as visions whenever he lets his mind wander or as dreams when he falls asleep, until eventually he will start finding ways of keeping himself awake until he can trust that it's over.