I think any only boy with a sister or sisters probably learns some invaluable lessons from the experience, like how to locate the key information in a too-detailed story; that the female ability to predict how long something will take or to define what on-time means can be different than the male version; and how what you say to a girl might be interpreted differently by her than how you meant it or how it would be interpreted by a guy: "What happened to your hair?" for example. Or the response: "Nothing." This discrepancy has led my husband to the phrase: "I actually
mean what I say."
I think my brother learned some valuable things from being the only boy among Katie and I.

He learned how to sense and avoid drama pre-episode, how to endure tedious and probably embarassing theater, music and dance performances, and he learned
the pleasure of scaring a girl really, really bad. I hope he realizes the debt he owes us.
I fully expect that Sammy, whether he gets brothers in the future or nay, will be able to trace countless benefits to the fact that he was born closely after Miranda, whom you can find by googling the term "girly girl." Okay not really but you get the idea.

But I should note that he's also experienced some drawbacks associated therewith.
One of these is "lack of boy dress-ups coupled with an overabundance of girl dress-ups." Owing to the generosity of relatives and friends sensing Miranda's propensity for drama (not difficult to detect, I might add), we have two drawers plus a couple of fancy hanging pieces of sparkly, floofy, high-heeled, accessory laden, feminine dress-ups.

I must acknowledge here the recent donation by our Stake President's wonderful daughters: gorgeous Mulan, Snow White, and Cinderella hand-me-down dress-ups. The Cinderella dress even doubles as Christine's dress when Miranda is playing Phantom of the Opera. (Fernando made a Phantom mask from half a white paper plate. The sheer genius.)
And although she sometimes comes up with less-princessy combos like this,

Sammy has been left scrounging amongst the dress-ups for unisex hats, scarves...heels...

And we love our son. So for his birthday his Daddy and I got him...

the 10 dollar Batman costume from Walmart. The pants and sleeves had to be hemmed and the mask is a bit big and droopy,
and we didn't buy the more expensive version with the puffy muscles (puhleeze people...fake muscles with the genes he's inherited? Scoff!). But he LOVES it. And when he's not wearing the mask he puts it on the front of his playskool car as a hood ornament and we have "The Batmobile." That's ingenuity the likes of the real Batman, I'd say.

And he's never even seen Batman.
That's how much he was longing for boy dress-ups.
Way to assert your manhood, son.