Toddler wakes up screaming on and off at night

My 16 month old is typically a good sleeper (as in we put him down and he goes to sleep on own), but lately (probably the last 1-2 months) he has had episodes of 2 hours or so of intermittent screaming between 12-3AM. It is not every night, but probably at least half the week. It happens regardless of nap times (he is in daycare so has low nap days and stays home sometimes with longer nap days).

He has had quite a few teeth pop up over the past month.. so maybe it’s that? It’s just like clockwork though. As soon as we go in, he settles. When we leave it starts again. We have tried milk, Tylenol.

Could this all just be teething?? Has anyone had this happen? It’s driving us nuts, and I feel bad for the poor babe.

Thank you!!