If you can give an example of any odd or unusual Silver has done lately I might be able to help better. But, try buying some meds at the local farm store to put on the wound. A topical med should do the trick to help heal and prevent infections.
~Idis
If the chicks are 5 weeks you should be able to safely separate them from her. But, if she continues to show aggressive behavior after they no longer cry for her she may be just enforcing the pecking order or fighting for female dominance (yes its a thing). If she gives any of the other hens a...
Runny poo is normal. In about every 6-8 stools you will have some. Sometimes your chickens may have eating something that caused it or, drank too much water. If this continues for more than a week or the poop starts to contain blood I would not fear.
Hope your chicken gets better!
~Idis
I can slightly see the affected area. From what I see I would say the same thing as before. If you add some activities for them like a range for them to walk around (if you don't have one already). Maybe look into hanging toys. They should be entertained by most chicken toys.
Your birds may be uncomfortable or scared. They will not roost for these reasons or, if your kids are constantly handling them. Please post vent pics as well so people can help out!
~Idis