i have a sheltie, that whenever i'm upset or crying, she walks over to me, plops herself in my lap and licks my face until i start laughing.
my sheltie is about 20-30 pounds (she's on the big end of the breed, i guess)  
i know she loves me,
or maybe she's just thirsty? 
  
sophie, my yorkie, is still so young.
when i cry, she just sits there -- turning her little head and cocking it to the left and right, its just too cute -- i have to scoop her up and forget all my problems.