Add space between specific facets in ggplot2 (facet_grid)

Question

I've been able to add vertical space between all facets (Alter just horizontal spacing between facets (ggplot2)) but haven't been able to add just one space between specified facets?

Here's an example based on my real data (in the real plot I have stacked bars):

mydf<-data.frame(year = rep(c(2016,2016,2016,2016,2016,2016,2017,2017,2017,2017,2017,2017),times = 2),
             Area = rep(c('here','there'),times = 12),
             yearArea = rep(c('here.2016','here.2017', 'there.2016','there.2017'), times = 12),
             treatment = rep(c('control','control','control','treat', 'treat','treat'), times = 4),
             response = rep(c('a','b','c','d'), times = 6),
             count = rep(c(23,15,30,20), times = 6))
mycolour<-c("#999999", "#0072B2", "#009E73","#000000")

Returns plot:

#default facet spacing 
example<-ggplot(data=mydf, aes(x=treatment, y=count, fill=response)) + 
  geom_bar(stat="identity", width = 0.5) +  
  scale_fill_manual(values = mycolour, name = "Response") + 
  labs (y = "Count") +
  facet_grid(~yearArea) + 
  theme_bw()
example

#spacing between each facet
spacedex<-example + theme(panel.spacing.x=unit(2, "lines"))

spacedex

How can I limit the addition of space to only between the second and third facet? (between here.2017 and there.2016)

Answer 1

library(grid)
gt = ggplot_gtable(ggplot_build(example))
gt$widths[7] = 4*gt$widths[7]
grid.draw(gt)