I currently have 4 broody hens setting right now. Macy, my muscovy was setting on duds as well, and I finally got around to kicking her off. She was behind a very heavy engine, so it was a tough one. She is the easiest broody to break. No eggs = no broody. I wish my hens were easier to break (only if it was January and letting the hatch in -20 is not a great idea (IMO anyway). The mothers would never stop sitting on their babies in that temperature.
I also have one hen with a brood of 7 as well. They will be 5 weeks old tomorrow.
Here she is with all 7 of her fluffy silkie babies
She only hatched one of these. All the other six were hatched by me in an incubator and raised for 1 week. Her one baby was a week old when I added the six others. Janet even accepted this random rooster chick that is 5 weeks older that made his way into her pen. She will take any chick. She does not care on the age.
She is not protective - I hate that.. She will run away if the roosters go after her, leaving her babies behind. If there are young pullets or roosters around her babies though, she will take jabs at them. She doesn't care if I touch them, and I've offered Janet some turkey from thanksgiving and she called her babies to my hand and they grabbed on to that turkey and hung there while holding on to the meat.
Anyway.. They are just so cute.. Janet is molting as well.. At least she is doing it while she is not laying anyway!