We have flock of hens, some 3 yrs. old, and some 2 yrs. old. One of the hens has been lame for a long, long time, and kinda "hops" around to get from place to place. There has been absolutely no problem from the other girls until this week. Several of them have been ganging up on her and pecking her.. Should I separate her from them for a period of time, or what is suggested for the problem? There was rooster in the gang until about 2 1/2 months ago, but he's now gone. There are 12 hens, who have never disagreed on anything. Please give me advice!