When did your infants sleep improve, let's say consistently 3+ hour stretches at night?
Was it a gradual improvement that took many weeks (how many)? Or was it like a switch got flipped, and it happened all of a sudden?
Eta: my little guy is 8 weeks (4.5 adjusted) and his sleep is suuuper inconsistent. If we're lucky, we'll get a 3.5 hr stretch. But usually he'll start crying around 1 hr and then we have to hold him