Screams after nap

Kaitlyn • 💙❤ Johnny Thomas ❤💙 02/10/17 💜💜 Angel in Heaven 💜💜 01/14/18 💖💖 Emily Joy 💖💖 01/26/21

For the last week or so my son (17months) wakes up from his nap in hysterics and doesnt stop for about 30 mins to an hour. Idk what the reason could be. he's not teething right now or anything... any ideas?