i have 3 children, first boy of 6 years & 5 months old, second girl of 4 years 5 months old and third boy of 2 years 6 months old. They doesn't talk properly( stammer and lisping ), there no one in family but they are why???? why does happen??? how to cure them???

A. For all the kids if you are facing the problem of stammering and all and not proper speech I would highly recommend you to consult the speech therapist once because there may be some problem with the speech of the child and maybe your child or kids I’ve had a lot of screen time that can also impact the speech please consult a speech therapist once