uneven scale does not hinder overactive imaginations.
So Barbie had a huge family of like 50 blonde people, with two brown-haired friends.. then there were the redhead girls that lived next door (two tyco Ariel dolls and my sister's old Strawberry Shortcake), and the fat kid from down the street (Cherry Merry Muffin's Banancy). So then Barbie and her family started being evil and decided they wanted to enslave the ponies from another land nearby and Barbie and Ken began cruising in their blue jeep making raids on the ponies and towing them away in their shoebox horse trailer. To make them work the farm and sell their pretty colored hair. The ponies couldn't really do anything about it because they had their own drama.. earth ponies thought they were way cooler than the pegasi and unicorns because they were actually super jealous of their abilities, so they usually kicked them out. Since the earth ponies couldn't do any magic or flying themselves, they couldn't create a good enough defense. Finally the sparkle babies got together (two earth ponies, a pegasi and a uni) and teamed up to outsmart Barbie and release all the kidnapped ponies. They did such a good job overcoming adversity and saving all the ponies of Dream Valley that even the stars themselves were proud of them. So the stars sent down magical sparkles that got imbedded in the ponies' skin, making the four of them extra special, but matching between them. Then they came down the hill and all the other ponies were like "oooohhh, ahhhhhh!" and so super impressed with the sparkles that it convinced them to stop being jerks to all the unicorns and poor Glittering Gem, my only adult pegasus pony.
Barbie also learned a lesson when all of her pets decided she was a horrible person and ran away to be with the ponies (this included 101 Dalmatians Pongo and Lucky from McDonalds, Oliver And Company's Dodger fingerpuppet from BK, a Pretty Kitty, a few random LPS, the purple mini elephant from the Animal Lovin' Barbie playset, Bambi and Thumper from McDonalds, two Secret Surprise puppies and an eraser shaped like a bird).
..yeah ..I had a lot of spare time when I was 8.