Ay normal lang yan, especially sa ganitong age! A few of us mums noticed the same thing sa aming babies, ang breathing nila talaga parang irregular pag tulog, mabilis bigla tapos babagal, parang they're still figuring out kung paano mag-breathe properly habang natutulog pa lang. Pero since baby mo ay 3 months na, mas safe pa rin i-check with your pedia just to be sure at para sa peace of mind mo, kasi they can listen better with a stethoscope and tell you if it's just normal newborn breathing patterns or if may kailangan i-monitor.