Cognitive development refers to your child's ability to learn, think, and problem solve. While it's important to know that every child develops at a different rate, typically by the age of two your child will be able to find items hidden under two or three blankets, they'll be able to sort items by shapes and colors, they'll be able to stack blocks about four blocks high, and they'll be able to point to familiar objects.
So that means if your mommy and daddy are in the room they should be able to point to them and they also should be able to begin to play make-believe. So it's really a great time to encourage opportunities for your child to either find things hidden under blankets, to stack blocks, and also to play make-believe with your child. Again every child develops differently but typically this is the milestones that are reached by age two in the cognitive area.