Lip tie

So my 5month old might have a LIP Tie. This is something I suspect and need to verify with a professional expert. My Pediatrician Seems not too knowledgable about it. Does anyone here know more about lip ties- mainly what are the consequences or implications of having one? Is it a defect and is it a major one? Do lip ties need correcting or do they resolve on their own? Do kids with lip ties also always hv tongue ties as well or could have no tongue ties just the upper lip tie? Any non invasive correction possible? And really WHY or HOW does it occur?