As a general rule, never hesitate to call your doctor if you have concerns for your child’s health and well-being. When it comes to the 18-month regression (or any regression for that matter), if you’re seeing it last well over a month go ahead and give them a call. There are some other signs you can keep an eye out for as well!
If your toddler snores very loudly, appears to have abnormal breathing, major changes in behavior, or other signs of sickness like fever, sore throat, and irregular glands, it’s best to take them in. These could be underlying symptoms of a larger problem. When in doubt, call!