The preceding-sibling axis selects elements that precede the
context node in the same parent element. For example,
/descendant::BORN[position()=2]/preceding-sibling::*[position()=1]
selects Elodie Bellau's NAME element, <NAME>Elodie
Bellau</NAME>. /descendant::BORN[position()=2]/preceding-
sibling::*[position()=2] doesn’t point to anything because there's
only one sibling of Elodie Bellau's BORN element before it. There's
no abbreviation for the preceding-sibling axis.