I Made Up an Illness to Avoid Babysitting My Sister's Kid

So, I have a younger sister who recently had her first baby. She lives across the country from me and my family back home, so when she comes to visit with her husband and the kid, it’s kind of a big deal. Usually, we all try to make it as fun and memorable for them as possible since they don’t get to see us often. This last time though? I was really busy at work and just needed some down-time, but no one seemed interested in stepping up to babysit her daughter during my sister's short visit home. So there we were, my parents, my partner, and me, all gathered around the dinner table for a quick family meal before heading out to meet friends of my parents' who had come to town as well. My sister was sitting right across from me with this expectant look on her face, knowing full well that it's usually my role to help out. But I really couldn't handle being responsible for someone else’s kid when I was already stressed enough. So the night before their arrival, I'd looked up symptoms of something mildly serious but not dangerous, ringworm, for instance, and made sure to mention casually while we were eating that I had developed a rash on my arm and the doctor thought it might be that. Of course, everyone’s first response was shock at hearing this news. But after realizing I'd come up with some random thing I read online, they didn't question me much. Instead of feeling guilty about lying, however, I felt a weird mix of relief and satisfaction for getting out of something I clearly wasn’t in the mood to do. When my sister heard, she just shook her head at me but agreed that we shouldn’t risk it, as her baby is still too young for anything. The next morning before they left to return home, she called me aside and gave me a hug while whispering thanks for not risking her daughter's health. But really? I had no intention of taking care of the child during their stay here anyway. Now every time we talk on video calls, my sister looks at me like I’m going to have to take full responsibility if she decides to move back closer with her family, which isn’t likely but still!, and every time I think about how easily I made up a condition to get out of something that was just more effort than I could handle then. It’s petty, sure, but it works for me.