With BronyDash465's permission, this is a rewrite of their original Orphans fic

Due to an engine malfunction on a train bound for Canterlot, Mr. and Mrs. Cake's children are put in the care of the one pony they trust above all others.

Now having to raise Pound and Pumpkin herself, Pinkie struggles with her emotions throughout their lives.

But if there's one thing she will not fail in honor of the ponies who took her in when she was a filly, that entrusted their children to her, it's that she will make sure the twins' grow up happy, for life is a party and nopony should be unhappy at a party