Nice work buddy! Though I don't see how SAI could have done that! O_O;; I can understand if it was flipped horizontal (i.e. if you press 'H' for shortcut key via keyboard), but there is no option to flip it vertically! XD Unless you drew this sideways from the start.
Nevertheless I heartwarming/sweet concept... I'm waiting for a follow up drawing of Silver and Blaze finishing it off... X3