17 months with DS1.
DS2 is almost 16 months and not yet STTN.
This doesn't mean they never had their nights that they slept through, but i def wouldn't have labeled DS1 as totally STTN until 17 months. A solid night of sleep was/is pretty rare. But we believe in gentle parenting, so i can honestly say there was no sleep training invovled. Though DS2 is high needs and sleeps w great difficulty, things are improving, i think his STTN days is coming to us soon. Which wouldn't surprise me since we follow their ques-it would make sense that they would be around similar ages per their body and such.