I have a chihuahua and a cocker spaniel could they possibly have puppies?

I don't know what kind of milk to give my chihuahua now that she is feeding three puppies because she doesn't have that much milk. Someone told me that baby formula but I don't know, what do you think ?
The puppies are one week old and the mom doesn't produce that much milk also she doesn't want to eat that much.

i want my chihuahua to have puppies but how old does she need to be?

My chihuahua is having puppies so can she still have relation ships with other dogs even though the puppies are still in her stomach?

my chihuahua is gonna have babies but she dont look that big..so i was wondering how big can one be when they are born?

My Shitzu is having puppies and the father is a chihuahua, what type of puppies will they be. (ex.- Pekichi, Pekipoo etc.)

How many puppies can a chihuahua have?

My "TOY" chihuahua is about to give birth. She is HUGE! Can anyone tell me how many puppies does a chihuahua USUALLY have in it's first litter?

I tried every store near me for dog coats.Don't say rude things please my dog loves them because it's warm for him because my room is cold and he has very little fur because it hasnt all grown it yet.He is a 15week chihuahua and about 3pounds and i can't find anything to fit him. I am willing to pay 5-25$ for it.I can buy off a site also i just cant find anything to fit him and i can't sew.

I'm asking cause I have a friend who has a chihuahua and she's around 6 months of age well she also has a male chihuahua around 1 year old and she noticed that her female was in heat already but she doesn't know if her female got knocked up or anything so she wants to know if she could still have puppies safely or will there still be severe complications.