Here is the issue as I see it: When you take on any pet, you make a commitment to caring for another living thing. One of the best lessons that I can teach my children is to honor their commitments and responsibilities. What kind of message would it send to just get rid of my dogs? It would send one of irresponsibility and one of not valuing living things.
I have heard people make all sorts of excuses like the dogs are crazy, they require too much attention, the bird screams too much. No matter the excuse, it isn't valid. You made a commitment. Honor it.
If you are worried, get to training your dogs or other animals before the baby comes! Remember to keep up training after the baby comes too. One of the best methods I have found with mine is to use a really high quality food as training treats. I know they are getting good food instead of the corn meal they try to pass off as dog treats, but they still enjoy it because it is different than their regular food. To keep treats readily accessible I used one of my rice cereal containers and filled it with the dog food. This allowed me to keep it on the counter without it being stinky and still readily available. (For other animals, using novel healthy food appropriate for the animal also works.)
Now for the most difficult part, catch them doing something good! That's right, any time you see good behavior that you want them to keep doing, give them a treat. Since you are giving them actual food, and small single pieces, you don't have to be worried about empty calories or unnecessarily high in sugar/fat treats. They will learn quickly the behavior you want. Ignore the behavior you don't want. When the kiddos do come, hopefully you will have such a great relationship with your animals that you kids can enjoy having them as part of the family too. All this being said, no matter how good your relationship is with your pets, do not leave your children unattended with any pet.
Keep your commitments and your kids too!