Let us know how she gets along. It is rare for anyone on this forum to tell you to cull, unless the chicken is a threat to the health of the rest of your flock. I really think this could be an internal laying problem. The hens can have problems standing for very long, prefering to sit, and may waddle. Symptoms can vary with every hen. Giving vitamins and minerals can be an easy treatment if it is somethingis wrong nutritionally.