Can I return cats to a shelter? Will they be put down if I do?

My husband recently adopted 3 cats into our home. He's very impulsive and didnt consult me before adopting them. I'm honestly not happy, I have a two year old and a newborn baby and im still recovering from my c section.. I'm unable to bend or lift anything heavy. I'm in tears because it's not the cats fault. I live in a Tiny apartment and they don't have any space.. I have to constantly protect the baby because they keep jumping on him and the two year old is basically torturing them because he dosent know any better he barely speaks and is learning to potty train. I'm really upset at my husband. He brought 2 kittens and an adult cat to our home 3 days ago. I told him that it's not right, he do this to us or the cats. I've never had cats dont know the first thing to do. He works and is gone All day leaving me to care for them. I'm really heart broken.. My family is across the country so I can't even ask them for help. I need advice I don't want them to get harmed if they're taken back or if they can even be taken back

Was it a high kill shelter? If so, they will be euthanized if it is a high kill shelter. If your husband didn't sign a contract with the shelter that he has to return them.. why not try to re-home them or find a rescue group that can take them and find them a proper home. 

I'm so sorry you have been put in this situation. It sounds very stressful.
The cats absolutely cannot be jumping on or near the baby, and it is highly possible your toddler could get badly scratched. The safety of your children is paramount and this situation sounds very overwhelming (and understandably so!). I think there is nothing wrong with temporarily putting all the cats in a closed room, like spare bedroom or large bathroom. Really, it will be less stressful for everyone, including the cats. If the cats have fresh food and water, and a litterbox, they will be okay until you can figure out what to do in the long term. A room with a window would be best, if possible, and throw in some toys to keep them occupied. Many people will isolate a new cat in a closed room for a few days to give the cat time to adjust to the new surroundings, noises and scents, so it is not uncommon or cruel practice.
You can return the cats to the shelter. In fact, most shelters make adopters sign an agreement saying if they ever decide to give up the animal, it must be back to the shelter only. And returns happen all the time for lots of different reasons, so there is no reason to feel awkward about it. In your case, I think this sounds like the best option, but that is just my opinion. You need to go with what you feel in your gut is best for you and your family.
And you never know, maybe after a few days of isolating the cats and everyone settling in, you may decide to keep one. When everything is not hectic, cats make lovely, calming companions. I can see how three, especially two being hyperactive kittens, is way too much at once.
I wish you all the best!

Thank u so much for the great advice. I will put them in my toddlers room and move my toddler in with me in the mean time. The room has windows toys and a bed I was just scared they would be stressed in a closed room. I think he got the cats from petsmart I will call them and ask if I can return them as a last resort in the mean time I'll try to find a home for them

If he got them from PetSmart, that is great news! The cats available there are offered by rescue groups, so they definitely will not be euthanized. They will go back to foster homes until someone else adopts them.

if you were going to keep any of them, I would suggest the kittens - you'll find they will more easily adjust to your lifestyle and if they grow up with your children, they will likely be best friends. Also, the two kittens will keep each other occupied I'm not sure what your hubby was thinking with the adult cat in the mix - is it the Momma? Or maybe he thought they would need a Momma When I had my firstborn, my Siamese kitten had to be wherever he was just so he could see Josh. It was kind of adorable, and he became Josh's best friend. Do they jump literally on the baby or are they just curious to see the baby and what it is? Do you know anything about the kittens' history? Are they littermates or bonded? It's tough with rescue cats. I have a 12 pound one year old 'kitten' - he really does still act like a kitten, and though he play attacks my feet a couple times a week (this is week 4 with him) my 2 1/2 year old granddaughter stepped on him and he never even tried to bite or scratch her. I think knowledge and protection of young honestly crosses species boundaries, however, in our human relationships there need to be boundaries, too, and it sounds like you're still feeling those out with your hubby I hope everything works out - I'm sure you will make the right decision for YOU and your family. The mere fact that you came here looking for support and information tells me you will.

That is very interesting, I would have strongly recommended keeping the adult. Unless the adult is fearful or aggressive. Well, fearful in the beginning but should settle quickly. Kittens are very active, they are far more likely to scratch.

Better yet, get in touch with Pet Smart, tell the the situation and ask how to get in touch with the rescue or foster home the kitties came from. You can find out all about the personalities. I promote adopting adults 1) kittens are easier to find homes for, but you don't really know what they will be like as they grow, friendly or independent, etc.  2) with an adult, what you see is what you get. They have gone through the stages kittens go through. More likely to already be completely litter box trained, less likely to scratch people or furniture.

The rescue should be the best ones to find homes for the cats. Although your situation does make me wonder. Good rescues generally check references and often do home visits. I don't know of a reputable rescue that would send three cats to a home with anybody not knowing the cats are coming and with such small children involved. 

Now, I've started thinking out loud, hopefully I make sense!

Please do contact Pet Smart and see what you can find out. I bet they can help you more than we can.