AMI Machine interview questions

Got a message through Indeed that they wanted to interview me for a part-time HR Coordinator role. I drove down there and interviewed with two people. A few days later, I got an automatic message on Indeed saying they went with other candidates which is fine because I felt their was a mutual sense that I was not the right fit for the position. For example, they are a small business and my most recent experience is with a 4000 person company. How I described my experience from my context is going to be apples and oranges compared to a small business. I also felt I was too green to take on the HR department of one role at the organization, and I felt the person I was going to replace felt the same way despite not verbally communicating it. I think what most caught me off-guard was being asked at the very end of the interview whether or not I have children and if I am married. Both of those questions are illegal to ask in an interview process. While I understand the person asking was just trying to be friendly and I was not offended, The fact that these questions were asked communicates to me that HR at the company is not adequately training up their employees and stakeholders on what is and is not appropriate to ask in an interview. Regardless of business whether it's a small business or corporate America, the same guidelines on what can and cannot be asked applies to all businesses. Don't get me wrong I thought both people I met with were kind, pleasant, and I was not offended. However, this type of questioning can lead them to trouble in the future because it only takes one person to take something the wrong way and boom you have a lawsuit.