Momshie, yan ay common talaga sa mga toddlers, especially during deep sleep, bubula lang dahil relaxed ang muscles nila at mas maraming saliva production, or sometimes it's just how they're positioned habang natutulog! A few of us moms noticed ito sa aming kids din, at usually harmless lang talaga, pero kung palaging ganyan or may ibang signs na off (like fever, unusual sounds, o difficulty breathing), better check with the pedia just to be sure. Basta monitor mo lang kung normal palang eating at playing niya during the day, okay na yan usually!