First, I hope the obligations that motivated your break turned out as well as possible. I once took a break to help my family as my grandparents' health took a turn for the worse and, while the end was sad, to this day I value that time immensely.
You'll need to have a solid, confident answer to, "Why did you take a break?" Are you comfortable talking about the reason for stepping away? If not, that's just fine. What's most important here is that you have confidence that you made the right choice for you, and that you project that confidence. For mine, it was, "I took some time to help my family as my grandparents were passing," but it could just as easily have been, "Some matters in my personal (or family) life needed my full attention for a while. I've settled them now, and I'm ready to focus on my career again." If they follow up wondering why (which they really shouldn't), I might say something like, "It's nothing related to my work life, and really no cause for concern, but I'm not comfortable discussing it."
Practice this answer, out loud, with a friend. Get yourself into a groove where you've said it enough times that you feel good about the sound and rhythm of it. Sounds corny, but helps you avoid feeling awkward and tossing in more details than you want to if they're quiet or seem curious, and it will guaranteed up your confidence in delivering it.
Meanwhile, did you do anything during this time that was related to your professional life? If so, you should consider putting it onto your resume. And again, if not, that's just fine — don't feel like you have to stretch yourself or the truth to make sure there's something on your resume during this time. Volunteering, working on community projects, etc. all might have relevant skills and experience that are worth including. Keep in mind, you're not looking to make the gap disappear via this, just sharing things you've done to continue to hone your skills and stay somewhat current.
Welcome back, and good luck!