girl shih tzu

Question
i have a year and 3 month old shih tzu and she's steadly humping which is telling me she is in heat i want to know is she old enough to have puppies

Answer
She's old enough to have puppies as soon as she's old enough to come into heat. That doesn't mean she should. I prefer to wait until after they are two years old. And humping behavior is always a sign of heat, sometimes it's dominance.
Good luck with your girl
Cindi