when do we learn to laugh?

My sister sent me this picture from her cellphone. It is of my 5 month old niece, Shyanne. She, too, will be a good laugher when she grows up, it seems, since she is already learning.
And below are both her and her big sister, Brittney in the pumpkin patch.

I have been spending more time with my sister lately and it is rad. I love watching her kids grow. It makes me look forward to having my own, even though my niece, Brittney (7) says I am way too old to have a kid. Silly girl.

