A Stillborn Two-Headed Deer

choi

(1) D'Angelo GJ et al, Conjoined White-Tailed Deer (Odocoileus virginianus) Fawns. American Midland Naturalist, 179: 299-302 (April 2018)
http://www.bioone.org/doi/abs/10 ... 99?journalCode=amid
(abstract only: the full report is locked behind paywall)

(2) Sandi Martin, Conjoined Deer Fawns Offer UGA Researcher Glimpse into Rare Wildlife Deformity. University of Georgia (in America, not the country of that name): UGA Today, May 7, 2018 (photo and X-ray).
https://news.uga.edu/conjoined-d ... wildlife-deformity/

Note: "Lab tests of the lungs confirmed the fawns never breathed air and were delivered stillborn"

That is because there was no air in the lung.