title: How to share facetgrid x and y axis using seaborn
body: <p><a href="https://i.stack.imgur.com/hEnNA.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/hEnNA.png" alt="enter image description here" /></a>Running this below code produces seaborn facetgrid graphs.</p>
  <pre><code>merged1=merged[merged['TEST'].isin(['VL'])]
  merged2=merged[merged['TEST'].isin(['CD4'])]
  
  g = sns.relplot(data=merged1, x='Days Post-ART', y='Log of VL and CD4', col='PATIENT ID',col_wrap=4, kind=&quot;line&quot;, height=4, aspect=1.5,
                  color='b',  facet_kws={'sharey':True,'sharex':True})
  
  for patid, ax in g.axes_dict.items():  # axes_dict is new in seaborn 0.11.2
      ax1 = ax.twinx()
      sns.lineplot(data=merged2[merged2['PATIENT ID'] == patid], x='Days Post-ART', y='Log of VL and CD4', color='r')
  </code></pre>
  <p>I've used the <code>facet_kws={'sharey':True, 'sharex':True}</code> to share the x-axis and y-axis but it's not working properly. Can someone assist?</p>