опять же с вашей ссылки - "Generally, if your child is strong enough to hold up their head, and big enough to fit into a helmet, they are old enough to sit in a trailer."http://www.mec.ca/Main/content_text.jsp?CONTENT%3C%3Ecnt_id=10134198673221371&FOLDER%3C%3Efolder_id=2534374302881813&bmUID=1270937016478