A distressed Abby sees a ray of hope in the care of her mentally unbalanced mother when she receives some sage advice from the older woman in a rare moment of clarity while Dr. Benton's old girlfriend Carla squares off against his new love Cleo. Elsewhere: Dr. Greene's suspicions are aroused when he treats a rebellious 7-year-old boy who bears signs of beatings; Dr. Carter's plans to apply for chief resident are brushed aside by Dr. Weaver while he watches fellow candidate Dr. Chen take her best shot at the position; Weaver suffers pangs of remorse when she meets the new woman in Dr. Legaspi's life and is confronted by a helpless, mentally deficient young woman whose only family member lies in critical condition; and the ER gang enjoys a spirited game of softball.