Paula Castaneda proud Mommy of 2 Female pitys and a female beagle/basset hound!

I have 2 adult female pit bulls, Boo who is my blue nose blue pit and halfpint my red nose. Boo is 8 tears old and halfpint is 7. I also have a 1.5 year old female beagle/basset hound. her name is Soapy Katrina. On Monday my boo gave birth to 5 beautiful and healthy pups. 3 boys and 2 girls. The end of her labor stopped at 730pm Monday night, or so we thought! This morning at 130am she ran to go outside to go potty and on her way out she actually gave birth to another pup, dead, fully developed, male! Then this morning at 900am it happened again! Both of theses pups were fully developed and just as big as the other 5 are right now. Can anyone help me to understand why this happened? Also should I expect anymore? :confused: