The quick reply is yes and yes. My understanding is that many of the behaviors often associated with BPD arise from the developmental hurdles that were not accomplished as children, and no doubt, because we were too busy surviving for one and Two, often lived in families that did not foster healthy growth. Many view it as a disorder of attachment and there is much written about that topic. My T explained that it makes sense that when we have young parts, we act the age we are in the moment. but if you look at that through the lense of adult expectations, well, you can easily see that it causes conflict with other adults. In the end, it's one more label and not as important as the reality of your individual situation. In therapy, it's all part of the healing process. Still, any T may choose different ways of working with issues so it will depend on your T's style, education and beliefs. You'll work it out together; it's a partnership. Best on luck to you on your journey.