Open-Mouth Sleeping

My son (almost three years old now) has slept with his mouth open since he was a baby, as well as just hang his mouth open throughout the day. Of course it was less noticeable as a baby since he used a paci, but it became increasingly noticeable as we took the paci away right before his second birthday. He drooled really bad as a 1-2 year old as well, and his speech and occupational therapist told me it was probably low muscle tone. However, he just had an evaluation with a different speech therapist who saw his open-mouth position and asked me if he did that often. He does not drool anymore, and is taking off in terms of speech. He has no problems eating besides being picky (no fine-motor issues). The new speech therapist told me it could be due to him having torticollis as a newborn and being a helmet baby. I am interested if anyone has experienced this and if there’s anything we can do?