Any Advice for a Parent of 6 year old who stutters every now and then

Any Advice for a Parent of 6 year old who stutters every now and then I have a 6 year old son who stutters but it is very noticeable at times and not so much other times. He is getting therapy with a speech pathologist once a week. When he is aware he is getting stuck (stuttering) , he is better at not getting stuck but when he is not aware is when he stutters but doesnt realize he is doing it. He does not stutter when he is reading out loud. Thank you for advice.