Why can my 4 month old sleep for so long?

I am afraid of posting this question because I know I will get the inevitable “just enjoy it, I wish my baby was like that” or “this isn’t a real thing and no one has a real baby like this”…

BUT I have never ever ever met a baby like my baby and as a FTM I guess I’m just overly anxious that I’m somehow damaging her?

Ok so. My 92nd percentile, EBF, almost 20lbs 4 month old went through her regression a couple weeks back. Like 8 wakeups a night.

She was hitting the sides of the bassinet so we put her in a pack n play in our room. But she just wouldn’t settle in it; the mattress seemed to hard and cardboardy for her so after a few days we gave up with it. I tried cosleeping for 2 nights, she slept great but my joints could not take it and I didn’t sleep at all from the anxiety I have about cosleeping (even when following the SS7).

I did not want to move her to her own crib and room yet, but we tried it out of desperation one night. I am anti sleep training, so I said as soon as she real cries, she’s back in our room. We didn’t even take the pack n play down for the first week.

But she did not real cry, even on the first night. I did not nurse her to sleep. We just did our bedtime routine (eat, bath, book, very short song from dad, and sleep suit) and put her in the crib. She stuck her thumb in her mouth and went straight to sleep and didn’t wake up again for 8 hours.

It’s been a few weeks since. She now sleeps 12 hours straight without a feed. We did not ever “sleep train.” She just loves her crib and room!

I was a parentified teen and room shared/took care of two newborns when I was too young to do so. They were formula fed and I still had to wake up SO OFTEN at night to feed them for the first 2 years and settle them to sleep. I still have chronic insomnia myself because I spent years catering to small babies and my sleep pattern never recovered. I know what normal babies are like, and I also hear the sleep schedules of my friends’ similarly aged babies and they confirm what I also experienced as a teen!

To be fair, we follow a pretty set schedule at this point. She eats on demand but it’s definitely lengthened to every 2-3 hours now, she takes 4-5 naps a day that are consistently exactly 45 mins long (also in crib). She gets a lot of active play time when awake, at least 10 mins of tummy time every wake window. We put her down roughly at the same time every night when she’s showing cues, sometime between 730-830 (9 at the latest if she took a nap too late in the day)…

I also know that at least for EBF, 4 month olds need to eat every 2-3 hours, which is definitely how often my baby eats during daytime, if not a little more.

So if that is true, what gives a baby the ability to sleep for such a drastically longer time without waking up hungry many times per night? How does that even work???