Everyone is different. You might be right about letting your guard down around family and friends but how much effort is it really effort to remain taking? Do you recognize it is NOT taking any to remain fluent in other venues? It might also be some weird psychological thing. I had an abusive childhood and always stuttered more with family, even siblings. I know it sounds improbable because you stutter badly around friends, too. Look into that ‘trying harder not to stutter’ thing. Then maybe talk to a counselor about any latent stress involving your family. Sue Good Luck, Sue