My Buff is constipated

I have a Buff that is little less than a year old. Her sister has been laying a while but she has not laid. This morning when I went to let them out of their coop, I threw some scratch out for them. As she was pecking around I saw her squat and strain a little. I thought she had pooped in her food so I picked up the rake to brush it out of the way. But no poop. I saw her do this 2 or 3 times. I was going to can't observe their toilet. But she seems ok, She eats as good as ever {I think} I have no way of separating them because there is just one small coop. I came to this pleasure a little late in life {I had kids, cats and dogs before}. Now I ha 2 hens and no money!! There is absolutely no way I can catch the chickens, they are too fast. Now when they want to come to me, it is a different story. When I sit outside in the summer, they jump up in my lap, on my shoulder, and even on top of my head! I have absolutely no one to help me catch them, nada. Should I just go out and buy some molasses? I have some white grapes here that gives the other hen just a little diahrrea, but if it will help....... She is a big fluffy hen but is a slow eater. She is at the far end of the yard now pecking away.She has fluffed herself up some, but it is cold and sprinkling rain so I wouldn't think that was a symptom. so has anyone else had an issue like this that worked itself out? Pardon the pun