Lazy or depressed?

I had adopted a kitten about 3 months ago, and right after I did that, I took a stray in. A pregnant stray, and I learned that because of the kitten nursing off of her

Anyways, I asked my brother to take one or the other, until she had her babies..He chose to take the kitten, and he now wants her for good, which I might allow since I have Squiggles and her 1 baby she had 6 wks ago.

So here is my question, She wont do ANYTHING..She was lazy before but I thought it was pregnancy, now the 6wks old kitten does 50% more then she does, she is only about 2 herself.

I had got about 100 different kinds of toys for the original kitten I got, and my brother left them behind, saying that Squiggles could have them..Well being that I have an assortment, from mice, to ones I play with her with, etc..She looks at me and keeps on walking..
Every once in a while at 4 am she jumps from couch to screens, to tables..With wild middle of the night behavior, but other then that she does NOTHING but eat and sleep

Any ideas? or recommendations, or is this just her?

Well, it usually takes some time for them to recover from having babies, but if you're worried, take her to a vet and see what they say, she could be missing something from her diet now that didn't matter before but does now (or any other kind of trouble).

Ok, she was at the vet when I asked, and all i got was "maybe its just the way she is"
And being that she was a stray, I have no idea what she has been through either, although, she has come up on my porch for atleast a yr, so she was always friendly, which made me believe she was someones outdoor cat, until she got pregnant and then they gave her the boot

Anyways, thanks, Ill see, maybe she just doesnt know what I am trying to do, or simply doesnt want to be bothered.
She was so affectionate pregnant, now she isnt, and she wont play on top of it all

She is going in soon for spaying, so Ill see how she even acts after that..
That is if this baby ever starts eating food!!!!
He's driving me crazy, I guess having one, he is too much a momma's boy, and doesnt wanna give her feedings up