This would be very uncommon - 4 months is quite young for a male to be fertile enough to impregnate a female.
as soon as she comes back in heat.....usually bout 44 years
Yes, as long as the chihuahua is "in heat" and they get "hung" (which you will know), the pug can get the chihuahua pregnant.
No.
My 6 year old chihuahua is pregnant by a 6 month old chihuahua. The vet said that the pups may not survive after birth.
A cat can get pregnant as soon as a few days after giving birth, so it's important to keep her separated from male cats to prevent another pregnancy.
No.
About six months.
A mother cat can get pregnant as soon as a few days after giving birth. It is possible for a cat to go into heat and conceive again shortly after delivering a litter.
No it is not normal for chihuahua to eat its puppies at birth
A cat can become pregnant as soon as a week after giving birth. It is important to spay or neuter cats to prevent unwanted pregnancies.
yes
I don't see how it concerns the chihuahua