Well, I have two children (little girls ages 3-5). I don't know what it cost's to do show/eventing, seeing that I was a little girl when I showed and well, my mom paid for all of that! BUT where I am from and where I used to get diapers (both my kids are potty trained now which I am soooo happy about), I got my diapers at costco, they are about $40 (that's after tax) a box. Diapers are expensive. I really can't say which is cheaper, but I also believe you can't put a price tag on happiness. We weren't "ready" to have kids, but I got pregnant, we made it work, was now the "perfect" time for me to get a horse, probably not, but we make it work. Lifestyle's can be adjusted, it's just about what your willing to sacrifice to make happen in life that's important to you. Do what makes you both happy, I didn't want to regret waiting to get a horse, so we did it, are you going to regret not having kids? Anyways, just my little opinion, good luck =)!!