Applejack had just left for manehattan to live with Aunt and Uncle Orange.  
Granny Smith turns to speak to Big Mac  
“You should get ready for school”  
Big Mac nods quietly and heads for the homestead. After preparing the things he needed, stowing them away in his bag, he heads on his way to ponyville. He sighed, without his young sis, This trip was lonely.  
Upon reaching the schoolhouse, Big Mac heads to the playground, to sit and wait for the bell.  
“Hey, Big Mac.” a voice calls  
The red earth pony turns and sees Brushed Brew, a younger gray colt who had recently moved to ponyville with his family. He and Big Mac had become quick friends.  
The younger colt trots up to Big Mac, easily spotting how he was feeling.  
“What’s wrong?”  
“Well ma sis, Applejack has gone off to Manehattan, live with ma Aunt and Uncle Orange. I guess I’m a little bummed.”  
After thinking for a little, Brushed Brew pipes up.  
“Come with me.”  
Brushed Brew then hurries off the other side of the schoolhouse, Big Mac gets up and heads after the colt. Rounding the corner, Big Mac is met with Brushed Brews rear-end stick up towards him, Brown tail lifted to the side.  
“My Momma would do this for me, when I feel bad.”  
Big Mac felt a sensation between his hind legs, as the young colt began to shake his rear-end, side to side.

imported from https://derpibooru.org/images/1520028