My parents are still married, and my mom's sister (aunt) is still married to her first husband, and they have two kids.
My dad was married before he met my mom, and he had his first marriage annulled. I'm not sure if my mom meant divorced or not, I never bothered asking for details. That'd come up as "I want to meet this lady that could have been my mom if you didn't step in" and would be just weird.
My mom has two brothers, one has two kids in his second marriage (none in first), and the other has one kid with his non-married "life partner".
So, analyzing this, only half of the four siblings have had kids in their first marriage and stayed in it, one married a guy who had been married previously, one got divorced and remarried, and one had a kid without getting married.