I remember when I kept hens when my youngest was about four. He loved eggs for lunch, especially yellow eggs (scrambled) or flat eggs (fried).
One winter, they had stopped laying (all twenty of the blighters) so I had to buy some shop eggs - battery at that as our shop didn't have free range. David asked for yellow egg for lunch. I dished up his scrambled egg on toast and he looked at it in disgust. "That's not yellow egg. That's white!" Clearly a boy with good taste.