Soon after the battle of Hogwarts, Molly is in the kitchen a day finds a basket of Fred's' unwashed laundry. She angrily yells "Fred"! for home to come down.
George instinctively disapparates from his room upstairs into the kitchen, knocking over the family's Floo pail hanging next to the hearth.
George and Molly's eyes meet across the kitchen table. His mouth bitter with the taste of Floo Powder, as he realised that he had just responded to a call for his dead twin brother.
The basket of unwashed laundry fell from Molly's hands and tears welled in the corners of Georges eyes. Those eyes were no longer quite so identical to Freds.