What Breed Are My Dogs?

You have three snuggies I'm sure!
It is very difficult to suggest mixed breeds unless you know more about them.
Age
Weight
Height
Body length

Pictures of body (sides) that includes tail
But everyone can voice an opinion and that may be helpful.
You say they are all under 10 pounds but a pure Chihuahua is 6.5 pounds or under (unless they are grossly overweight and yours look like they are a healthy weight). The 6.5 pounds is set by the AKC and their web site states that if your dog is over 6.5 pounds it is not a pure bred Chihuahua but a mix.
Your pups can have a lot of Chihuahua but most likely have another breed and that could be any number of different breeds and whatever we 'guess' could be correct or not - the same as your thoughts about your pups.
Of course, only a DNA test could tell you for sure about your pups breeding but being 'for sure' is probably not something you need to know about your pups.
I hope they all have their shots/vaccinations as not having these can be dangerous for your pets health.
Vet visits can sometimes be expensive when several pups are involved but shots can also be obtained at most of the Tractor Supply & Farm Stores but also at your local PetCo and these can save people a lot of money.
Of course, shots should only be given to healthy pets.

www.thriftyfun.com/What-Is-My-Chihuahua-Mixed-With-2...