Any suggestions?

I have belgian malinois - 3 at the moment. One is a 6 month old foster, very gentle and submissive, definitely NOT the problem. I also have a 9 year old male, same temperment as the puppy, not a problem. Then there's my 5 year old female malinois (she would be considered sharp). She is not accepting the puppy into the household. I've been introducing them gently but I still would not trust her around the puppy if I didn't have her on a leash. If I can't get this resolved I'll have to place the puppy. I'm looking for others suggestions. Thanks!!

Is the new pup female?
If so, your answer may be to find a different foster for the pup.
Often females just don't get along

If not, I'd probably crate the pup and just keep up with slow introductions

Yes, the foster pup is a female. I know it is hard sometimes to have two or more females together. Still, I was kind of hoping that we could work it out somehow... Thanks for your suggestion though.

Some dogs are going to be much more aggressive on a leash or in a crate being introduced (and yes, cage aggression is very common - take a walk through a kennel and witness normally good natured dogs).
What I would do is take the puppy to a nuetral place. let the young pup run around in say a ball feild. Bring in your older female with a basket muzzle on. Let her loose in the feild and let them work it out. The older girl may be so preoccupied with the muzzle that she will have a chance to get used to the smell of the new pup and smell the pups "regions" haha. This is the best way, also some people make a mistake when they introduce dogs that they put the dogs on leashes and let them spot each other from a few feet face on. That is never a good idea, dogs need to smell the privates of each other to get familiar. Females are not hard to introduce and especially if you have a really easy going young one. The older female may set some rules for the younger pup but, normally they sound worse than they actually are. Normal dogs will try not to physically harm a young dog. Perhaps even give the older dog some rescue remedy to ease her before being introduced.
good luck

Thanks for the advice. Where can I get rescue remedy? I've heard of that before and had been thinking of giving it a try. Also, the muzzle idea is a good one. I'll let you know how we make out!

I found rescue remedy at my local health food store. It was in with the liquid tentures.

Well I bought Rescue Remedy tonight but won't get to try it for a few days. The puppy is at the vet as she was just spayed today. I won't be allowing her near my other female dog for a while. I'm ready to try this though when Lacy is healed from her spay. Thanks again for the suggestion. Looks like I can try this when I'm stressed too! <grin>

I have a friend that uses it for her dog and herself!!

I wish you best of luck with your dogs, go slow and hopefully the two will settle in with each other.

Thanks for the encouraging words. Lacy, the puppy, came home from the vet yesterday (she was just spayed). So it will be at least 10 days before I attempt to put them together.

you are going to think this is crazy but could be the smell of your new pup
bath the pup and put her close to your 9 year old male (try to get his scent on her)
your 5 year old female might just be rejecting the smell from your puppies previous inviroment - hey it's worth a try

Hi GSDMom, well I can say that I have never heard of that before but I'm willing to give it a try. She could use a bath before winter anyway. I'm not ready to give up on this situation yet although I know that placing her would be very easy. It's funny, my 9 year old male and the puppy play together fantastically. After I saw that I realized that I needed to try to make this work, the older male is my soulmate, a wonderful dog. My 5 year old female doesn't play nice outside, she gets too "turned on". She's a very high drive girl, probably should have been a working dog.

I appreciate all of the suggestions and will work my way through them.

One last item to suggest, be calm when introducing. Take 3 deep breaths and act as though this is the most natural thing in the world. Most dogs pick up on their owners stress and will pinpoint it to the newest environmental change = puppy.
Muzzle, neutral territory, calm owner walk around and keep in mind that the older female can body slam the new pup, but, she can't bite her. Let them work it out and set their new boundries. You'll probably see the puppy roll over onto her back and expose her belly to you older girl. This may go on for a while and the older female may growl and stand over the pup every time she rolls over. Very normal behavior. Once the older female has established her self and her superiority over the pup things should be fine. I would take the muzzle off when it seems the older female starts ignoring the pup, or goes into play bow.
I have done this numerous times, females are quite easy to get along. Most times the older female can be grouchy for awhile, but, she's only trying to prove a point

This sounds like good advice! I do try to stay calm but I'm sure they are picking up on a little of my unspoken apprehension. I am going to wait at least another week before I get them together again since the puppy was just spayed. I can see little changes in the body posturing of my older female and I think she is relaxing around the puppy a little. They can get nose to nose at the gate but usually the puppy knows to stay back away from it. Luckily neither girl wants to jump the gate.

New minor problem with the puppy, since coming home from the vets she doesn't want to go in her crate. I'm thinking that she was traumatized by my leaving her at the vets and of course she was kenneled there. We are working gently with the crate now and I did get her to eat her dinner in there. I got in and encouraged her to get in with me while she ate.... geez it's just like raising kids!