Vertical alignment of lyrics to multiple voices

[Jack Cooper]

Happy new year!

I have been navigating the lilypond world for the past six months and have
been primarily exploring lilypond as a tool for creating leadsheets and songbooks.

My main interest is figuring out how to create an efficient template
for creating a leadsheet (or "fakebook" style sheet) for all types of modern
guitar-vocal based songs.

I am wrestling with the formatting for lyrics.  I am aiming for a modular approach
to constructing lilypond input so that I can format sheets for a wide variety of 
song styles.  The main problem I am having is the vertical alignment of lyrics 
assigned to one or more voice contexts.  I will start off with a small example
to exemplify the problem.  In the following example, I am printing off the melody
and lyrics to "Frere Jacques".  I creating separated voice contexts for each
"section" of the song, and am assigning lyrics to each section.  The
 resulting
output properly assigns the correct lyric to the correct voice, but the
different lyrics are rendered on the same vertical line- each successive
lyric is placed lower than the one preceding it.

How do I change this so that each lyric snippet is vertically aligned?  All my
keyword searcing through the archives and manual hasn't come up with
anything that seems to work (I've tried overriding the minimum-Y-extent and
Y-offset of the lyric context with no discernable change).

Any suggestions welcomed!

Thanks, 

  Jack

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code snippet:

 \version "2.8"
 \include "english.ly"


melodya =   {
     \clef treble
     \key c \major
     \time 4/4
     c'4 d'4 e'4 c'4 | c'4 d'4 e'4 c'4
 |

}

melodyb = { 
     e'4 f'4 g'2 | e'4 f'4 g'2 |
}

melodyc = { 
g'8 a'8 g'8 f'8 e'4 c'4 | g'8 a'8 g'8 f'8 e'4 c'4 |
}

melodyd ={ c'4 g4 c'2 | c'4 g4 c'2 \bar"||"}

 

melody = {\new Voice = "a" {\melodya} \new Voice = "b" {\melodyb} \new Voice = "c" {\melodyc} \new Voice = "d" {\melodyd}}
  
texta =  \lyricmode  {
Fre -- re  Jacqu -- es,
Fre -- re  Jacqu -- es,

}

textb =  \lyricmode  {
Dor -- mez Vous?
Dor -- mez vous?

}

textc =  \lyricmode  {
Sonn -- ez les ma -- tin -- es,
Sonn -- ez les ma -- tin -- es,

}

textd =  \lyricmode  {
Din, din don!
Din, din don!

}

 \score {
    <<
  
     
    \new Voice = "whole" {\new Voice ="a" {\melodya} \new Voice="b" {\melodyb} \new Voice="c"
 {\melodyc} \new Voice="d" {\melodyd}}
                           

    \new Lyrics    \lyricsto "a"   \texta
    \new Lyrics    \lyricsto "b"   \textb
    \new Lyrics    \lyricsto "c"   \textc
    \new Lyrics    \lyricsto "d"   \textd
     
     >>
     \layout { } 

}

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