The short answer is Yes, it is possible. The longer answer is Maybe. You could pass it on only when you are shedding the virus, which for most people is only a small percentage of the time. The catch is that if you never get symptoms (no blister, rash, redness, itching, tingling, burning, etc.) then there's no way to know when you're contagious. And even if you do get symptoms, it's possible to shed the virus between OBs and not know it.
However, if you've had it for a long time and your life is pretty unstressed (stress being one of the major factors for creating OBs), you probably don't have to worry much. Another factor to consider is that a vast majority of people (an estimated 50-90% depending on a variety of factors) already have HSV-1 (typically orally), usually caught in childhood from non-sexual contact with family and friends. So your friends and nephew may already have it anyway.
So coming back to the short answer again: Yes, it's possible but it's probably not necessary to go to extremes about protecting others. Some common sense is helpful but not paranoia.
Hope that helps!