Over Protective Mama

Question
I am the proud owner of a female German Short Hair Pointer, Seger who did an amazing job carrying and whelping 10 healthy, beautiful puppies.  She gave birth on Nov 16, 2007 and to date we have found great homes for all 9 - knowing always that we would be keeping one.  At 10 weeks all the pups were gone and we felt as though Seger was adjusting well.  However lately with the weather warming up (spring in the mid west) more and more walkers are out in our neighborhood and we have noticed how over protective Seger is now of the pup.  Before the puppies she would sit on the edge of the yard and watch as other dogs & people walk by...or if barked or jumped around...out of pure desire to play.  Now each time the hair on her back stands up and she barks alarmingly.  There have even been times, she has literally pushed Sinatra (her pup) back, maneuvering herself infront of him, as a barrier between the passerby and the pup.  In the 2 years we have had Seger I can vaguely remember a true growl...and yesterday she growled at a familiar neighbor who was walking on our side walk.  We have buried electrical fence that keeps her from going on the sidewalk, but it is alarming to both my husband and I. We have a very active neighborhood and do not want to fear an incident.  Any ideas on how to calm our baby?  Thanks!

Answer
Probably the best thing to do,is slowly have her spend less and less time with the pup,like sometimes putting them in separate rooms in the house,or having one outside and the other inside at different times-this doesn't mean they can't be together,just not all the time,so she will learn that the pup is ok on it's own