personal comment Back when I got my first Pokemon game (Blue) I always picked Squirtle. And I wish I could get him in my Pokemon White 2 but I don't want one who been made by hacking so it's a bit difficult.
Anyway so I felt like doing something other then an Animation I haven't done that for a while even tho it's not an animation I hope you like it ^^
I think there is a way to get squirtle on White 2 without a hack. If you have leaf green of fire red on GBA you can get the squirtle (not sure if that game can trade up to diamond and pearl) but pokemon from sapphire, ruby and emerald GBAs can trade to diamond and pearl without hacking, to just transfer it if you can. But you need an old-style ds with the GBA slot as there is a trade feature in diamond and pearl lets you do this. you trade them up and re-capture them in this special pokemon reserve area.
If you've managed to get it to that DS platform then trading to white 2 is easy enough, but it still takes a few game cartridges and consoles. Just saying; it is possible but tricky to get squirtle on that game without a hack.