@andreea777 The wake window stuff is the
only thing I use from "sleep training" because it makes it easier to know when the babies should nap for/how long so they aren't over tired/not tired enough.
However, sleeping straight 12 hours a night I feel like is serious bull. My daughter sleeps MAX 10. Then naps anywhere from 1.5-3 hours. I wake her at 3pm no matter what and she is usually ready for bedtime routine at 8:30, in bed by 9.
She has lower sleep needs, however, and that we've had to learn through tons of trial and error. We also somewhat let her set her own schedule, if that makes sense?
If she wakes at a certain time we adjust nap time and bedtime some if needed. She also has learned because of this that if we are out and about, on the rare occasion it runs into her nap time she knows one of us will just pick her up and carry her so she can nap or she'll nap in the stroller.
Anyway, I know sleep is hard for small kids and parents, and I offered my input to my SiL regarding his wake windows. I told her 3 hours does not seem like nearly enough time awake, especially with a 4 hour nap, and her excuse was, "well daycare never wakes him if he sleeps that long, but they always cap it at 3 hours." And I said, "I think that's what's recommended for his age range. Plus since he's at daycare, he's running around and constantly stimulated. He's on vacation right now, so he needs more time to get his energy out.
Anyway my words were ignored, which is fine I know unsolicited parenting advice is annoying for anyone so I didn't push too hard, but it was still very upsetting.
Edit: I should add that we co sleep so while we follow wake windows loosely, we adjust as needed and go with her cues and flow. Some days she's more tired, and some days not so much.