Feral mom and babies

Im new at this, so bare with me...About 2 months ago we had a stray cat that would not leave our complex balcony. On the second night of her being around we let her come into the apt and then we would put her out when we left for work. She even used the potty outside like a dog!! It was almost too good to be true. We determined that she was definitely pregnant. She was extremely friendly and loved to snuggle and be petted. She even slept on my stomach a few nights. When she gave birth two weeks ago, she woke me up, laid into me and proceeded to have her kittens on my bed with me there with her.
After they were born I moved them from my bed to a box near food and water as suggested by all I change the towels in the box once a week and give her fresh water everyday. She still comes and cuddles with me time to time too
The kittens are two weeks old now. They all (4) seem to be in good health and mom seems content...until the last two days. She doesn't sleep in the box too much, but prefers to lye on the floor in front of it. She gives out a lot of short low tone meows, but I figured she was just communicating with her babies. Yesterday she tried to move one kitten behind the couch....it's an unsafe drop, so I took the kitten from her and brought it back in the box with its siblings. When I left for work today I put pillows behind the couch so she couldn't get behind it. When I came home 2 of the 4 kittens were out of the box, but only about 2 feet away from it. When I approached the kittens the mom began to lye down to feed them, and then when a different kitten mewed from the box, she popped up and went in the box, so I put the other two kittens back in the box. She didn't seem to mind too much. I fed her like I always do when I get home, she ate just fine and then went in the box with all 4 kittens.
The kittens are growing and definitely more active now.
Should I get a bigger box? I know all websites say its normal for the mom to move them, I'm just worried about where she may put them when I'm not around.
Is there anything I can do? Or am I just worried for nothing? The mom is still affectionate twords me and I plan on getting her fixed and letting her decide if she wants to stick around. I have good homes lined up for the babies when they are ready also.
Any suggestions would be great. Thank you for taking the time!!

So literally after I posted the first post I went to Che k on the cats and they were ALL out of the box. One had even gotten under my bed...which is super full of dust bunnies. This is making me really nervous, so I put the box in the corner where the mom had moved the kittens, put all 4 in the box while mom watched. After I moved my bed back into place i made sure the box was more secluded in the corner and I petted the mom for about 5 minutes trying to reassure her everything was OK. I fed her some wet food as a little treat too.
Her moving her kittens is really freaking me out. I don't want them to eat or inhale dust/dirt.
I'm sure I'm being paranoid. My roomte keeps reminding me that if she had the kittens in the wild they would be in way worse conditions.... BUT IM STILL FULL OF ANXIETY!! IM WORRIED. Any suggestions or advice would be great!!!

Can you block off under your bed? I think she's trying to tell you it's not what she wants anymore.
My girl who has some three day olds keeps putting them in the most silly places.
I also suggest getting a larger box and perhaps even shutting the door while you're out if you can.

They are outgrowing their box and ready to move around more. Mom apparently is done with the box.

Lots of cats love to nest under beds. I suggest that you clean under your bed so they can go there without any worries. Under the bed is actually a safe, dark, private place for cats.

I also suggest that you close them in your bedroom when you are not home. Put mom's food, water, and litter in the room for easy access. They do not need the run of the apartment right now. They should, in fact, be content in the bedroom for several more weeks.

Mom will want them all completely out of the box to nurse on the floor or under the bed. As it does no harm, just let them. No need to keep returning them to the box. They've already outgrown it. Be careful where you step though!

Mom will likely make a very nice house cat after she is spayed. Do not let her outside until the kittens are weaned and she is spayed, as she can get pregnant again.

Please do not re-home the kittens until 8 and preferably 12 weeks. This gives mom time to teach them kitten manners and they will make better pets.

Your dust bunnies comment reminds of when we first got Eclipse.  He was 10 or 11 weeks old. He found every crack and crevice imaginable.  He spent the first month covered in dust and cob webs. I had no idea how bad it was under the bookshelves!

Thank u all so much! I will definitely be cleaningnunder my bed today! Wood floors get so dusty! Last night after I moved the box, I slept in the couch to give her some privacy. She came to cuddle with me on the couch! Made me feel more at ease. She hasn't moved them from the box again. I was worried to close them into my room because its been getting so hott! Its suppose to be 101 today Our small ac unit is in the front of the apt so I leave that on and put a fan in the hallway to circulate. Do t worry I will not be adopting out the kittens until they are ready. I told the new homes at least 10 weeks if not more.

Sounds like she moved them to be closer to you.

Just got home from work and all 4 kittens are still in the box next to my bed, and mama was happy to see us when we walked in the door. Thank y'all for the advice !!

It sounds like mom is settling in. Glad to hear they are all doing well.

I've recently had the pleasure of momming a stray cat and her babies. Mama was prego when she first arrived, and I plan on getting her fixed and keeping her around, one kitten also I know not to give the kittens away until they are weaned from nursing, at about 8-10 weeks, but I'm surprised at how fast its gone by.
They turned 7 weeks yesterday and basically run our household.3 out of 4 of the kittens eat both the wet and dry food, while easing up on nursing. The 4th kitten seems comepletely uninterested in the wet food while barely nibbling on the dry food, and definitely nurses more than the others. She finally just started hanging around the other kittens when I feed them the wet food, but she just drinks water instead.
We had planned on waiting a few more weeks to rehome the kittens and fix mama, but I'm worried about the kitten who is nursing the most.
Is there something I can do? I'm not trying to rush them, but Im not sure how long is too long for them to be nursing. Maybe I'm just being a worried mommy, but I want to make sure they are all on the right track.

There always seems to be a laggard, but in general, kittens will nurse as long as mom will let them. I've kept a pregnant stray and all 4 of her kittens, and they nursed for almost 4 months, even though they were on solids. I think you'll see this kitten moving more to solids soon. They all get there sooner or later.

Would love to see the family

So today we said goodbye to two babies. Mom is in a good mood. I've been giving her extra love For now we still have two and most likely they will be gone within the week. The pic below are the two that left today.
How do I know when I can take her to get fixed?

They look so sweet! Are you keeping a kitten?

Mom can be spayed anytime now.

Im not 100% that I'm keeping one. We'll see. I read that if I fix her to early she can have complications if she has to much milk still...is this true?

The surgery is easier for the vet to perform if her milk is dried up, but as the incision is made between mammary glands it is frequently done while a cat is still lactating.

I had my stray mom fixed when her kittens were 8 weeks old. She continued to nurse for a couple more months. There were no complications and of course, no more heat cycles.

Ok. What kind of recovery should I expect for her? The only other cat I had got fixed when I was 6years old, and I don't remember. My work schedule is a little funky, so I want to make sure I don't leave her unattended.

Best case scenario would be a Friday morning surgery, and bring her home the same afternoon. That's what I did with my cat. Then you're around all weekend to give TLC. She'll rest and sleep a lot for a couple of days. Ask for pain meds if the vet doesn't offer. About 3 days' worth should be sufficient.

You said your work schedule is funky, so you just need a day or two off AFTER she has her surgery, whatever day it is that works for you.

Most cats recover quickly - kittens even faster and without pain meds. My cat returned to nursing immediately.

Everyone is doing great! The two that went to a new home at 10 weeks are enjoying their new family. Everyone is happy and healthy. Mama has also been acting more and more like a house cat everyday.I took mama to get fixed yesterday and everything went well. This morning mama is acting like herself. She was cuddling and purring all morning. I brought one kitten into the room cuz i felt bad keeping them apart. She was fine in the beginning licking and smelling her kitten, but then started to hiss and swat at the kitten...I thought she was trying to play at first,but when the kitten went for the water bowl mama definitely got mad. I picked up the kitten and left the room, mama followed but then went right back in my room to lay on the floor.
I closed the door to give her some more time by herself.
Is this behavior normal after getting spayed?

She could be in pain.  Did the vet give you any pain medication?