First litter of kittens...what to do?

Hello, I am a new grandma to 6 kittens and up until about 5 days ago Pixie and her kittens were on my back porch, up high and doing fine.
I came home after spending a day in town (I'm usually only away for a couple hours) to find that Pixie had moved her kittens.
She is an outdoor cat and I've usually always had my cats spayed or neutered. I didn't even realize Pixie was having kittens till about a week and half before she had them. I happened to pick her up and knew immediately that she had kittens in that tummy. (Pixie doesn't like to be held, she likes to be petted as long as you don't pick her up).
My problem is my husbands dog. Very excitable, lacks discipline and loves to chase my cats. The cats on the whole don't mind as long as he isn't trying to walk on them in all the excitement. (large dog). Pixie is ONLY frightened of his size. She will lay and sun herself right where he is roaming around, she simply keeps an eye on him but doesn't move. Other times she will run from him. I suspect that it was due to the dog that she moved her kittens? He had never bothered them and was very careful of Pixie when she was PG. But I can't figure out any other reason she would move them unless she thought they'd outgrown their home. Or could it have been my neutered male (Cong) who wasn't happy with her presence much less a litter of kittens! They are 3 1/2 weeks old and if the dog was the cause what are the chances I'll ever see the kittens again?? Or is she hiding them from the male cat and if so can't the males find them if they want to??
I'm know nothing about cats, can you tell?

Cats will move their kittens when they feel threatened...and it will be hard to determine the exact reason....however, she has decided her kittens are better in a different location. Does she come and feed at your house?? If so, you can continue to feed her....when the kittens are old enough she will bring them over to feed as well. At that point, I would have her spayed. Otherwise, she will become pregnant again. Is there a no kill rescue you can get in contact with to place the kittens once they are weaned from mom?

Katie

Hi thanks for answering, Pixie isn't a wild cat she was a gift and yes she comes to eat 3 or 4 times a day and I called the Vet to find out what to feed her. Thanks for letting me know she will probably bring them to her eating area I was worried they might go wild if she didn't bring them back. I plan to have them all spayed and neutered when the time comes and I will have no trouble finding good homes for these kittens in my area. Thanks again.

She also will move the kittens if the nest becomes to soiled and starts to smell. It is very difficult to find kittens outside, unless mom wants you to find them. I would just keep putting out good food for the momcat- start putting out kitten chow, and canned kitten food about 7 times a day if you can, because she will need the extra nutrition, and just trust that she will bring you the kittens when they are old enough to eat solids- that is about all you can do. And she will more than likely be pregnant when you do take her to get spayed so just prepare for that possibility. Also talk to your husband about obedience classes for this dog and add one more command to the program NO CHASE!

I appreciate all your help. I took special care to make sure her sleeping place was clean after the kittens were born. After much thought and watching her I finally came to the conclusion that she probably moved them for more space, they were growing quickly and her bed wasn't all that big. She hinted, but I missed it. The vet and I have already discussed the possiblility that Pixie could be PG again before she is finished feeding this litter. We have not yet decided on what we want to do about that. All 6 of her kittens will be 'fixed'. Pixie is getting plenty of food. I feel like that is all I do is take food out to her, thankfully my daughter told me she would need a lot more food and boy, she wasn't kidding! And the Vet told me to make it kitten food. Meantime I will take the bull by the horns (or the dog by the scruff of his neck) and teach hubby's dog the 'no chase' command starting right now. thanks again for all the advice ladies!