$ sudo apt-get update
$ sudo apt-get install liblightdm-gobject-1-0 

liblightdm-gobject-1-0 is installed in your system.

Make ensure the liblightdm-gobject-1-0 package were installed using the commands given below,

$ sudo dpkg-query -l | grep liblightdm-gobject-1-0 *

You will get with liblightdm-gobject-1-0 package name, version, architecture and description in a table

liblightdm-gobject-1-0 package basic information: