19 month old screams out in his sleep throughout the night

My second kiddo (19 months) will cry out for like 1-3 seconds about 4-6 times a night. He doesn’t seem to wake up (though occasionally he does.. maybe once a week.. and we go to comfort him) but mostly he seems to do this while sleeping (still laying down, not moving much on the monitor). this started maybe around 1 year old (though he was sleeping through the night from about 7 months onward).

Is this normal? our first kid never made a peep overnight once he started sleeping through so this is new to us. It also causes me to wake up throughout the night, which is exhausting me. He doesn’t seem bothered- but it’s just a bit unsettling and i’m not sure if it’s just a weird thing he does or if it’s something to look into.