A late submission to this thread! I wonder if Ms. Gregg could be the Carson Jane Doe. The UID was found in 1978, two years after the disappearance of Ms. Gregg. Since MP was last seen after giving birth, is it possible she ran away, uninterested in motherhood at such a young age or was possibly taken against her will? Either way, this could account for the 2 year gap between her disappearance and the discovery of the Doe. The Does postmortem reconstruction strongly resembles her and was said to have likely given birth which aligns with Ms. Gregg's distinctive physical features and context of her disappearance. The MP was reported missing a roughly 7 hour drive from the UID which is a reasonable distance to travel in the time frame, especially if Ms. Gregg hitchhiked. I've attached an image of Ms. Gregg (left) and the Doe (Right) for comparison. Thank you for giving these women a moment of your time!!
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