I had a similar problem with my son but he was hitting anybody not just family. All i did was put him on a naughty step as soon as he hit out, i dont give him any warnings, if he hits he goes on the naughty step regardless. It worked and although when tired he might do it occasionally in general it has stopped.
Well i have a naughty step but it can be anywhere in the house where the child is removed from everyone like a naughty corner or even a naughty room if your house is big enough! Write a list of rules on a big piece of card i.e 1 no hitting, 2 no kicking etc and stick it on the wall. If any of those rules are broken he goes straight to the naughty step for a few minuites (its usually 1 minuite for every year of the childs life). Get a timer and set it for however many minuites and say that he cant get off until the alarm goes off, if he does just calmly put him back on and start his time over again. It can take a long time for it to sink in when you do it for the first time but stay calm and just say that he broke ur rules so thats what happens. When he knows what the naughty step is all about you can then start explaining to him that he has always got a choice i.e when you can see him getting angry tell him that he can choose to hit someone and go on the naughty step or he can choose to walk away and find a nice toy to play with. I think this helps them to feel a bit more in control and it might take a while but if you keep at it and keep calm (easier said that done i know!) it will eventually sink in. good luck, i do sympathise with you because ive been there!
Looks like your naughty step is what Americans call time out. I had just started doing that to him when he licks something or spits on the floor. I was just not sure if this was OK with the hitting habbit. Thanks for your advice and will let you know if it works.
