Muffin may be pregnant again

I found Muffin and Biscuit locked up today , we thought she was in heat but wasn't sure. SO this morning when I saw them locked up I knew then that we'll probably be expecting another round of puppies. I then did a Gestation calculation using this site http://www.schaferhund.com/pregnancy.htm

According to the calculations puppies should be here on Sept 21st 2006. Last time the calculator was dead on the money. Anyway with puppies coming along in late sept they should be ready just in time for Christmas. This will be the last round of Peek-a-Poo puppies, we've decided to get Muffin fixed after this one . It's not fair to her to keep having puppies, and we never wanted to start a puppy mill. Although the money from the puppies is pretty good, she means more to us than that.