Image imported from derpibooru 
Original Description:
 
If you don’t know what’s going on, browse my gallery until you find something about Rainbow Dash and Soarin’.
 
At some point, Smithy decides to attend a Wonderbolts show, even though Rainbow Dash tried to convince him not to. Smithy wondered why this was. While sitting in the stands, he sees a teal Pegasus mare, who looks very familiar. (I’ll add the link to why Smithy recognizes Lightning Dust)
 
Afterwards, he sees one of the Wonderbolts hug the mysterious mare, and goes to ask where he’d seen her. Gale offered an autograph, and was shocked when he claimed to be here for her mother. He introduced himself as Smithy Gold, and Lightning Dust suddenly recoiled. “What is your family name?” She asked
 
“Apple-Dash”
 
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At Sweet Apple Acres, Rainbow was bucking trees when she spotted a mare trotting her way.
 
“Hello. Can I help you?”
 
“Actually, you can. Are you Rainbow Dash?”
 
Rainbow was confused, and considered for a second if she should answer the mare.
 
“Yes.”
 
“My name is Gale, and I was sent by your son.”
 
Had he found out? Had something gone wrong? Why does Gale look so familiar? Many thoughts were running through Rainbow’s Head.
 
“Smithy?”
 
Gale nodded.
 
“He recognized my mother, you see, and told me this is where I could find you. You see, I have something very important to ask you.”
 
“Who is your mother?”
 
“Lightning Dust.”
 
Rainbow started to lightly pant, putting a hoof to her head, and wiping off small drops of sweat.
 
“I know nopony by that name.”
 
“But you did. And I am here to ask you for forgiveness.”