Your situation with outdoor-only dogs sounds very different from what we are used to in the United States and Western Europe, but it's not uncommon in other parts of the world. It wasn't even uncommon in the US prior to the 1970's.
One of my concerns would be around the relationship between the female puppy and the female dog you plan to adopt. In general two female dogs are more likely to get into fights than a male/female pair or even two males. You said the puppy had bite marks from fights. Was she being used as a bait dog? Does she have poor social skills? Did she come from a household where the senior dog was vicious? I wonder how traumatized she is from her prior experiences, and how she will behave in response to her trauma. Meanwhile, the three legged dog may feel vulnerable due to being crippled and unable to defend herself properly. She may not deal well with a puppy that has poor social skills. Some timid dogs deal with their fear by declaring "the best defense is a good offense." So, watch for issues when you bring the new girl in, especially when the puppy gets to the age when she is due for her first heat. Things may be fine if all the dogs have sound temperaments (we once had a dozen dogs including 5 females living in a two bedroom cottage,) but you need to monitor the situation.
One of my concerns would be around the relationship between the female puppy and the female dog you plan to adopt. In general two female dogs are more likely to get into fights than a male/female pair or even two males. You said the puppy had bite marks from fights. Was she being used as a bait dog? Does she have poor social skills? Did she come from a household where the senior dog was vicious? I wonder how traumatized she is from her prior experiences, and how she will behave in response to her trauma. Meanwhile, the three legged dog may feel vulnerable due to being crippled and unable to defend herself properly. She may not deal well with a puppy that has poor social skills. Some timid dogs deal with their fear by declaring "the best defense is a good offense." So, watch for issues when you bring the new girl in, especially when the puppy gets to the age when she is due for her first heat. Things may be fine if all the dogs have sound temperaments (we once had a dozen dogs including 5 females living in a two bedroom cottage,) but you need to monitor the situation.
