gym rat

hello everyone
this thought has been in my mind for 3-4 months now, i am a bit cunfused and maybe have some issues with it. i grew up in a family of 5 with an older sister(2years older), myself(male) and a younger sister(3years younger), mother and father. we where all pretty privat. door locked when having a shower, bedroom doors always closed. didnt see any one of them without any close on, didnt dare to try to peek.
i am now 34 married with 2 childeren, 7 year old boy and a 5 year old daughter. my wife was an only child and saw her mom and dad naked all the time, bathroom, bedroom all indoors of cource.
when it is bath-bed time for my 2 childeren, they run all over the house naked, this doesnt bother me a whole lot, but my wife let them bath together a little while ago and i got home from work i went to check up on them and started going crazy and got them out of the tub and in to pjs. i just thought they where too close to each other. i am not against nudity and i dont want them to grow up feeling ashamed of there own bodies.
how do i or we(my wife and i) go about seperating the time for nudity and privat time. ive been on some interesting forums lately and read some different stories between brothers and sisters and it bothers me to think of what could happen because they see each other naked at bath-bed time.
i am interested in hearing what others think in this situation, good or bad.
thank you for your time, sorry it was soooo long or if it is confusing. my writing sucks
gym rat