New home, new friends

(water bottle shown for size comparison, not for kitten food or bedding!)
As you know, or maybe you don't know, I love animals and will feed any creature that shows up at my front door looking hungry. For the past 8 months or so, I've been feeding a stray cat that I call Butternut, as well as her grown-up kitten Sprinkles, and a male cat. They have gotten so friendly and tame that they will just walk right in the front door and into the kitchen to get a snack, and sometimes jump up on the couch afterward to be petted for a little while. Well, a few months ago, Sprinkles had some kittens of her own. I was hoping to pet them, but they're pretty skittish and we still haven't been able to get close to them. We figured that Butternut wasn't able to have kittens anymore because her hips are kinda messed up and her tail just kind of dangles there, she can't lift or move it.
And then one night last week it stormed. While it was raining, we heard a strange little sound, like a bird. Husband got up to look out the window on the front door and didn't see anything. So he opened the door and said "OH. MY. GOD." So of course I ran over there. There on the doorstep, taking shelter from the rain, was Butternut. Next to her was the tiniest black and white kitten I've ever seen, mewing pathetically. We scooped them up and dried them off and put the kitten in a box with a towel. Butternut was pacing and acting weird, so we let her out after a while. She didn't come back, so I decided to sleep on the couch with the kitten box next to me so our other cats didn't interfere with it (earlier Bijou gave it a good bop on the head...). Husband had an early shift and left around 4:00 in the morning. Butternut still wasn't back. But around 7:00, I was awakened by a familiar sound... I opened the door to find a tiny, shaking orange kitten all by herself, crying. I sighed and picked her up, dried her off, and put her in the box next to the other one. Obviously they were siblings, as they curled up next to each other and went to sleep right away. Sure enough, a couple of hours later, Butternut returned and came in to feed them. And now, almost a week later, they are still in the apartment.
It was all adorable and I love kittens, but we already have two cats. Plus, Butternut decided to bring them the week before we give up that apartment for our new one. The selfish part of me wants to keep all three of them, but that doesn't seem very practical. It's like a cat soap opera around here, honestly.
Well, I'm glad I can enjoy playing with kittens at least for a few days :)