What will happen if I breed a Half Shi-tzu Half Maltese with a Chihuahua? Is this possible?

I have a Blue Chihuahua (they are not actually blue but silvery gray) and was planning to breed it with a Half Maltese/Half Shi-tzu. First off is this possible? And second off does anyone know what I would end up having. Also, how long does it take for the female to give birth after pregnancy. Thanks for any answers.