Which one? Where?
Ah, oh that? Well, where do you think ponies come from? http://assets.sbnation.com/assets/592610/Gimli.jpg These are advlt ponies with advlt needs, you know? Anyway, they aren't making love in that picture, they're cuddling, and recovering from wasteland-induced trauma. The lovemaking must have happened before or after. I will also draw your attention to the fact that those two are both mares (female). Bucks have squarer jaws.
Yup, I got that. I understand completely why the two ponies are having six in the story. Looking at it purely in the context of the story it makes complete sense. What I don't understand is the genre. You have Fallout: targeted toward mostly mature audiences, and My Little Pony, which is targeted toward kids (6-11 year old girls, give or take?)
So are these Fallout fans, (that being advlt-ish people who play gory, violent video games) who have decided to make the story go all cutsy with the Pip-Bucks and Unicorns... or are these My Little Pony fans, who've decided that they want to see ponies get exploded, and thrown into these situations? Judging by the level of writing and artistic skill, I could guess that it's the former and I just want to know why. Why My Little Pony? Why Fallout? At this point it's just honest curiosity.
And on a side note, when the developers were origannly designing My Little Ponmy, yes. They were going to go with the idea that the ponies sprang out of the ground, or rainbows or storks or from magical cloud dust. I doubt any of the fan letters to My Little Pony asking where Clip Clop came from involved a line about the birds and the bees.