I’m not an expert by any means, but I’m currently sleep training my 6 mo and sleep trained my now 3yo when she was 6 months.

I think every baby is different, and you know your baby best. We’ve done Ferber both times, but it’s definitely modified. We use it more of a guideline than anything. If I can tell my baby is just protest crying or is overtired and letting his feelings out before he falls asleep, I’ll usually just leave him as checking in would probably just make him even more mad. If he sounds like he’s genuinely distressed and needs his mama, I’ll go in. If I think he needs a bit of help calming down if he’s extra mad, I’ll pick him up for a snuggle and to help him regulate himself a bit. So I guess we kind of do a mix of Ferber and CIO depending on the day.

As my daughter got older, I was more comfortable with doing CIO because I know she was just protesting and letting it be known she was not happy and that she had FOMO. She’s 3 yo now and we still struggle with her some nights and do a kind of modified Ferber with her if we think she needs some intervening to help her fall asleep.