Sight and smell not all that important with chick ID in chickens. It is all about sound. Follow what I originally suggested keeping the chicks she is rejecting very close to her where she can at least hear them and they can hear her. Chicks need to imprint on her as well. I have been putting my chicks in a minnow trap with food and water. Then wedge the trap right next to hen sitting on nest or in a box. Listen for clucking of hen and chicks to synchronize. At end of day remove chicks from trap and place them under her for the night. Check on them first thing as lights come on. To test, pull chicks in question out about 6 inches from her and see if she clucks to call them back with them retreating to be under her belly without being pecked.
I have a broody hen with two 36-hour old chicks and some 5-day old chicks in brooder that could be used to demonstrate for later similar issues. Hen and her chicks are white while brooder chicks are black.
I have a broody hen with two 36-hour old chicks and some 5-day old chicks in brooder that could be used to demonstrate for later similar issues. Hen and her chicks are white while brooder chicks are black.