A. For Tansystar and Briarripple's father, find the FallenClan cat named Beestripe (she's left of their camp entrance+has yellow fur with black stripes) until she stops giving you new dialogue. After that, talk to Hawkfeather again, she'll point you to the farm. You can't fully go to the farm, but you will encounter a fence+a cat lying down. Talk to her until she has no more new dialogue, then talk to Hawkfeather again.
B. For Robinfur's headaches you need to find a way to access the coldstone.
Hope this helped :D