This seems a most unusual point of view to me. I'm in a few different mom's organizations, and it seems to me that at least 50% of our discussions are about our kids.
I'm sure my opinion is unusual though in my experience not uncommon among parents of kids with disabilities (perhaps more than "slight" as you mentioned). I'm sure what you are describing is very common for moms' groups which is why some people find them irritating and promoting of parental insecurity.
I don't think it is uncommon to find people who gas on about the ages their children accomplish milestones as being irritating. We attended one playgroup where such talk dominated the conversation. Sure, most were clever enough to be creative about the way they presented the conversation "I'm really wondering if Susie will have trouble with reading since we are in a bilingual household, she's already sight reading some of course..." or "Junior just won't watch kid's programming but of course he's always just been so advanced..."
What's going on with them, challenges we're facing, and what milestones they are reaching. It's not really 'bragging' per se, but mostly about sharing our excitement about our kid's development. Watching kids grow and learn *is* exciting.
I've been interested in the moms who enjoy their kids but aren't reciting milestones. Let's have a conversation about books, restaurants, a happy moment yesterday, how tired we are...all of that stuff is more supportive and more interesting to me.
I don't see it as an introvert-extrovert question. I'm very extroverted, but I don't think my child's life and his accomplishments belong to me to brag about, to blog about, to define my identity by. I don't see what makes my child worth loving, worth carrying about, worth talking about that he was 3 months early in sitting up or making a two word sentence. That seems like nonsense to focus on. It tends to make most people who are out of the middle of the developmental bell curve feel bad and I don't see what it accomplishes in the process.
Maybe my perspective is different because I have a teenager and I've seen that being very low key is the long term road to having people in your life support your decisions. We've received absolutely no flack for our kid being PG and being radically accelerated . We don't hide, but share as it comes up in context and don't talk milestones. It has worked well for us.
