We're talking about two entirely
different scenarios here.
- Women aren't born with large vaginas. If a woman has never had children, it's highly unlikely that her vagina will be too big. However, vaginal muscles can become loose after childbirth, making satisfying sex a little difficult. Kegel exercises have been known to help enormously with this problem.
- Some men are unfortunate enough to be born with penises that are so small that they make sexual intercourse either impossible or extremely frustrating and, even, painful for their partners.
It's possible that the woman in question was just trying to get some ideas from her friends about creating a more rewarding sex life, rather than deliberately demeaning or shaming her H.
I hate to say it, but you're wrong
It's a myth that vaginas change 'size' because of childbirth (or god forbid, many partners).
It CAN, and does occasionally, depending upon the birth itself, but it's actually just as common that a woman's vagina becomes tighter afterwards as opposed to bigger. Usually they return to normal (if there was any muscle damage to begin with).
The thing is, muscles repair themselves. People who lift weights know this. They become bigger because you are literally damaging them, then repairing, damaging, then repairing.
"After you workout, your body repairs or replaces damaged muscle fibers through a cellular process where it fuses muscle fibers together to form new muscle protein strands or myofibrils. These repaired myofibrils increase in thickness and number to create muscle hypertrophy (growth)." - the first web page that came up when I googled it.
Childbirth can change the muscles in that area positively, negatively or not at all. There's no pre-determination that a woman who's had 8 kids will have a huge vagina, versus a woman who's had no kids.
Now what is true, for many women, is that the vagina will change size over time (ie. age). As most of us lose muscle mass as we age, it's perfectly normal. This is why Kegel exercises are important, especially as we get older. They work on men, too.
As far as being 'born' with a large vagina/penis - of course we are, it's genetics. Obviously they grow into adulthood, but it's pre-determined, just like the size of your feet, or your ears, or your nose.
So, a woman can partially
control the 'size' of her vagina through something like kegel exercises, but the reality is that it increases the strength of those muscles and her ability to squeeze and/or control them. Same way a gym rat lifts weights. He/she can gain some solid muscle mass, but it's only as long as they continue it. Those muscles will be lost if they stop lifting, and return to their normal state. A woman gives birth, and whatever happens to her vaginal muscles will, more often than not, return to the state they were prior. They may also not, and her vagina will be looser, OR they will repair themselves in a way that makes her tighter.