Yes it does - either by drugs/alcohol while their mother was pregnant or even depending on how long it was before they were adopted as a baby. That separation from a birth parent can cause a trauma wound even if they were “only” a month old etc. Not to mention if there is a birth family history of severe mental health issues like you mentioned. My ex’s daughter was diagnosed bipolar (most likely hereditary since her mother and grandma also had it), and then also was diagnosed with the attachment disorder as a child which then became a borderline personality disorder diagnosis when she reached adulthood.