Holeshot staffies

We currently have 1 female and 1 male English stafford in our family and we are looking at purchasing another female pup. But we don't know if the 2 girls will get along. They are pets first and formost so they will not be locked up most of the time but we do have an enclosure that one can be in while we are not at home but I don't want to favour any of them over the other. Are we just being silly or is this something we should be looking into more?