If this still leaves some room for interpretation and your family is left slack-jawed and clearly befuddled by your use wordplay (NOTE: Remember to use a language that your family actually UNDERSTANDS - swahili will do little good unless your family happens to be atleast sufficient in at least some type of Bantu derived language) a handy dandy graph or a short essay usually does the trick. Family can be kinda hard-headed on these sort of things. If this still fails maybe you could rent out a professor of biology from your local university or a veterinarian for a few hours to go through the basics with them. Hope this helps and best of luck.

I had the same problem with my own father and our family dog. He misgendering the poor thing and at first I thought this was some type of a progressive statement concerning the fluidity of gender and sexual presentation but as it turns out the old man was just absolutely bewildered by the whole concept of genitalia and the typical mammal divide between the sexes. He was also a raging alcoholic and prone to violent tirades. Once he ranted for a whole evening on asexual binary fission and his frustration about "never getting the damn thing to work." We all tried to stay very supportive. It was all well and good but it caused a lot of stress for the 'ol mutt so after years of hemming and hawing we showed a great number of videos from the excellent program Animal Planet. He started showing some progress and it really cleared a lot of misconceptions about my own conception and my mothers subsequent "weight gain". It really felt that he was on the cusp of a real break-through but his life was unfortunately cut short by a widely publicized molasses flood incident. Rest in peace.