\version "2.18.2"

upper = \relative c'' {
  \clef treble
  \key c \major
  \time 4/4

  e4 g8 g e4 c |
  r1 |
}

lower = \relative c {
  \clef bass
  \key c \major
  \time 4/4

  r1 |
  d'4 d8 d d4 d8 d |
}

text = \lyricmode {
  Three lit -- tle In -- \set associatedVoice = "lower" dians, |
  Four lit -- tle, Five lit -- tle, |  % How to show this?
}

\score {
  \new GrandStaff <<
    \new Staff = "upper" { \new Voice = "singer" \upper }
    \new Staff = "lower" { \new Voice = "lower" \lower }
    \new Lyrics \with { alignBelowContext = "upper" } \lyricsto "singer" \text
  >>
  \layout {
    \context {
      \GrandStaff
      \accepts "Lyrics"
    }
    \context {
      \Lyrics
      \consists "Bar_engraver"
    }
  }
  \midi { }
}