Proto-Halfling language

Proto-Halfling was the ancestor of the Halfling language and its various dialects. Since the Halfling language is quite conservative in its grammar, and hasn't had too many sound shifts in the last millenium, it is difficult to exactly pinpoint where does Proto-Halfling end and a form of Halfling that could be described as "close enough to the contemporary" begin, although the definite point of transition is usually put at the 9th century BEKE, when the proto-language fragmented into clearly recognizeable dialects that still remain mutually intelligible to this day.

Evolution from Proto-Norlokian

 * The distinction between the sibilant fricatives and affricates  shifted towards a distinction between postalveolar  and alveolar . They would be realized as affricates word-initially, after nasals and when geminated, fricatives otherwise.
 * All of the plosives developed lenited allophones  in postvocalic positions, but only when ungeminated.
 * The flaps became trills  when word-initial or geminated.
 * The schwa became silent, unless it would have created a consonant cluster larger than three consonants (or two word-initially), or word-initial plosive+plosive, nasal+plosive, nasal+sonorant, sonorant+plosive clusters. In other words, word-initially, only sibilant+plosive, sibilant+sonorant and plosive+sonorant clusters were allowed word-initially.
 * In contaxts where didn't become silent, it became  after slender consonants,  after broad consonants.
 * The glottal stop became silent. If it formed a consonant cluster with any other consonant, it put compensatory lengthening on it.
 * Vowel shifts:
 * Monophthongization: →
 * A-fronting:

The Transition
The consonantal system of Early Proto-Halfling was not very stable. One of its more fragile elements was the allophony between plosives and fricatives, especially sibilant affricates and their fricative counterparts.

First, the sibilant affricates lenited to regular fricatives before any consonant - even in word-initial clusters. Inconsistent and unsystematic removal of word-initial short vowels in some very commonly used words, as well as prolonged contact with languages that contained word-initial fricatives: namnely, Archaic High Elven and Proto-Human. This cemented the status of those fricatives as separate phonemes from their plosive counterparts. Their voiced counterparts never became separate phonemes.

Vowels
Unlike the consonantal system of Proto-Halfling, the vowel system was rather stable and didn't really change during the course of the language.