Once Alpha, but now passive

Question
Our four-year old female Yellow Lab had her first litter in July 07.  We kept one male pup.  The pup is now 9 mos.
The mom was always the sole attention-getter before the pup came.  Now she seems depressed because the cute pup aggressively seeks and gets our attention.  The mom would always sleep in our bed, but now the pup sleeps there, and mom stays on a bed in another room and pokes her head out once in a while.  In the mornings, she usually would sit on my bed while I get ready for work.  She would not come out of the other room until finally I had to carry her on to my bed.

The pup usually stays in the outside kennel during the day while mom is inside, but even when the pup was outside, she would not come out of the room.

Despite giving mom a lot of attention, she will gently wag her tail when she first sees you, but she does not seem happy like she once was.

I am certainly no expert, but am wondering about a couple of possibilities for her recent change in behavior:

It has been a long winter and now she has become used to not getting too much exercise and has gotten used to being lethargic.

She has sadly stepped aside, and her pup has now assumed the alpha dog role?

Any thoughts/advice?

Thank you.  

Answer
You have unfairly (and inadvertently) promoted that puppy over his dam. Immediately demote the pup.  Create a sleeping area away from your bedroom and that is where the pup will sleep for at least the next few months.  Additionally, immediately begin using positive reinforcement training on this puppy (not quite a puppy any more) because you have effectively psychologically promoted him and he most likely perceives YOU as lower ranking.  This could develop into other behavior problems related to dominance/rank opportunism.  As soon as you have obtained a 100% successful and reliable response to one command, make him earn everything for at least two months.  This will put him in his "place" and make him more emotionally secure, as well as teaching him some cognitive skills.  Also, have this dog neutered immediately.

The Labrador is a breed specifically designed genetically to interact with humans as a subdominant member.  Without clear structure, these dogs can get into substantial trouble.

While you are in the process of creating a companion of your younger Lab, allow your female to sleep wherever she wishes.  She might, eventually, return to her "nest" in your bedroom (which is the place of most importance in your home.)  Have her SPAYED.  Unless you are breeding to improve your breed (with substantial knowledge of genetics) there is NO REASON for her to suffer any further pregnancies.  It's obvious you have no working knowledge of dog psychology.  Your female has suffered an enormous psychological and emotional punishment in the past year.  She requires some TLC and needs to be protected from further exposure to physical, emotional and psychological stressors.