Spike and Twilight Sparkle are from Hasbro's My Little Pony: Friendship is Magic and this screenshot's taken from Valve's Garry's Mod.

This takes place in an alternate universe where Twilight is actually Spike's mum instead of sister. The dragon kid walks to hug her and is like "I love you, mama." and she responded "I love you too, my little Spikey Wikey."