Analyze all potential liability and defenses

Scenario:

Dorothy invited her next-door neighbor Patty to come over for a cup of tea. On the way to Dorothy's house, Patty did not use the sidewalks, but instead walked through a gap in the bushes along the side of Dorothy's yard, and then through Dorothy's flower bed to short-cut across Dorothy's lawn. To step into the flower bed, Patty had to step over a rope hanging along the bushes about two feet off the ground. As she was crossing the flower bed, Patty stepped on a piece of metal sticking about two inches out of the ground; this piece of metal pierced through one of her toes.

For several years, Dorothy had an irrigation system to water her grass and flowers, and used the services of ABC Lawn Service to maintain her grass and flowers. A few months ago, ABC Lawn noticed that the flower bed was being trampled by foot traffic; thus, with Dorothy's approval and to discourage persons from walking in the flower beds, it strung around the flower bed and bushes the rope that Patty later stepped over. Two weeks before Patty's visit and unbeknownst to Dorothy, ABC Lawn Service had damaged the irrigation system and left a piece of metal from the irrigation system sticking out of the ground in the flower bed next to the bushes. This is the same piece of metal that pierced Patty's toe.

Patty went to a hospital for treatment for her toe injury. Patty was in extreme pain and was traumatized at the thought that she may lose her toe. While at the hospital, Patty contracted a highly contagious and deadly infection that had been spreading in the hospital. The infection led to her being hospitalized for two weeks where she suffered a great deal of pain, and then led to her death. The hospital knew that Patty's infection was very contagious; indeed, four of Nurse Terry's co-workers had recently contracted the same infection, although it was still undetermined how those co-workers had contracted the infection. Nonetheless, the hospital forced Nurse Terry to treat Patty anyway. Nurse Terry also contracted the same infection while employed by the hospital and treating Patty. Although she did not die, Nurse Terry was bed-ridden for three months from the infection. Patty is survived by her husband, Hank, and her son, Sam.

What theory or theories of liability might reasonably be asserted in each of the following actions, what defenses should reasonably be raised, and what party is likely to prevail?

Hank and Sam v. ABC Lawn Service

Hank and Sam v. Dorothy

Hank and Sam v. the hospital

Nurse Terry v. the hospital