Mind your own dang business

So last night a bunch of us went over Aunt A's for dinner because Aunt B was here for the week for work/training. I walked in the door a little late because we were babysitting all day and J didn't leave until almost 6pm. When I got there I hear my mom talking about...can you guess?...surprise!!! WORK. Good grief she just HAS to make sure everyone knows how horrible it is and how miserable she is in her job. We get it Mom. You've been unhappy at your job pretty much FOREVER so is it really necessary to bring it up in EVERY conversation??? Geez. Anyway, dinner was delicious and afterwards we sat down for a game of Apples to Apples. It went okay. I won, haha. In the middle of it Shiloh was taking out most of the cards we weren't using and putting them on the coffee table where we were playing. She ran off to play something else and C said, "Um Shiloh you should come clean these cards up." Shiloh came back and started gathering the cards. She got about halfway through and her little 4.5 minute attention span distracted her and she walked away to play again. Now, for the record, I was going to make her clean up the rest before we left anyway so it didn't bother me that she walked away in the middle of it. As Shiloh walked away C said, "Um Shiloh you need to come finish cleaning up," to which I responded (laughing), "Yeah well that's about as good as your gonna get with a 4 year old attention span!" THEN I hear her mumble something under her breath. I said, "What?" She said, "I don't agree." WHAT?!?! Are you...an unmarried, childless woman suggesting how I should handle my own kid?!?! HOW DARE YOU. All I said back to her was, "Yeah well she's not your kid." I wanted to say more to her but the whole family was around so I held back. I may have to talk to her about it at some point because the whole thing really bothered me (and still is bothering me). Why is that people who don't have kids feel such freedom to step in and tell the PARENT what they think they should or shouldn't let their kid do? I'm tired of "defensive" parenting where I feel like I need to jump in and stop certain behavior (even though most of the time it's just them being kids) because I know "someone else" is going to jump on them. I've been feeling like I need to run interference with certain people (mostly my sister AND brother at times, especially when L is around). It's getting REALLY annoying and makes me not want to be around any of them anymore.