This is what Luna do right alther to come back form pony ville alter nightmare moon and be turn back to normal! celestia be happy to see her little sister back to her and home and save!  
Luna: hahahahahaha! come on sister! come play!  
Celestia: yes luna!hehehehe!thanks you twilight  
Luna: Sis?  
Celestia: oh! oh sorry luna! i be think of of somethink! do want eat some cake?  
Luna: yes! is be 1000 years i not eat a royal cake? hmmm? i hope the cake will good as those i…no we both togeter!  
Celestia: yes Luna! little the one we both eat! i ask to make sure the resipe be save for your return!  
Luna: yeah! let eat the Sun&moon cake!  
Celestia:hahahaha! i love you luna!  
Luna: me to celestia and i sorry for the past! i promesce to make sure this nightmare never hurt us or other pony!  
Celestia: yes you are right! and let do it togeter!

sweet pic.