I would remove any new eggs! She may sit on them for awhile and start the process of developing chicks but she will abandon the new eggs to tend to her babies already hatched. My hen did that as well. She also had a few eggs that did not hatch on day 21 and 22. on day 23 she kicked them from the nest. I thought it was an accident because she had 10 babies under her and was trying to make room. when it happened x2 more the same day I decided to open 1 egg. I turned out to be a dud, not even a blood break so I opened the remaining 4 all duds. Plus the fact that mama hen has had limited food and water during her 21+ day nesting. Asking her to go longer would not be good for her health as she will probably do a heavy molt soon. As for the babies staying with the flock? Everyone has an opinion. Growing up my grandma had chickens in her barn. She never separated them or moved them (nests were close to or on ground). The mama started teaching them from day one. I brought my hen and eggs into the house until they hatched after the first chick only got 1/2 way out before ants attacked and killed it. Mama herself was covered in ants and had left the nest. So I cleaned her up and brought mama and remaining eggs in until they hatched except for the duds. Then moved her and babies in a dog crate with solid side but bars on the door so the flock would adjust to mama being back and babies. 2 days later I let them all out but monitored close the first day. No problem. They are just over 2 weeks now and go in and out with mama and the flock.
