Young visitors to Adults only sites

I was considering a site in a region I wanted to visit and found that it was for adults only.  My first thought was "how small minded some people are...", but then a more practical thought hit me; would my infant grandchild be allowed to visit us on site?  We try to caravan near where our grandchild lives (170 miles away) for this very reason.  Could anyone please advise whether it would be a breach of rules if my grandchild were to visit us while staying there?  The family would not be staying overnight.