Technically, hers wasn't a case of conjoined twins; she had a parasitic twin.

Dominique was born with a parasitic twin.

The girl was born with a parasitic twin; she had an additional two legs and an arm extending from her abdomen.

Known as foetus in fetu, the condition occurs when a deformed foetus is absorbed by its sibling and becomes a parasitic twin.

When I'd seemed unenthusiastic about Kurag's proposal, he'd dropped his pants and shown off both his own equipment and that of his parasitic twin.