Alfred

Just send a bunch of onesies, bibs, pacifiers,bottles maybe, bottle cleaners, maybe a hat or two. Babies pretty much need the same kinds of things all over the world. And just because its hot doesn’t mean he might not wear a light weight long sleeved shirt. It’s hot and the sun is probably an issue and I’m not sure how young you can actually put sunscreen on a child. I hope it helps!

Madilyn

Hey, I’m moving there in May!! We are currently in Puerto Rico, so I can advise you very well!
Socks are actually ok, especially because inside, the AC is often cranked pretty high. After a while, babies do get better at regulating their body temperature, but I used socks all the time for at least 6 months with my daughter.
Lots of short sleeved onesies are perfect, basically a uniform here! Short overalls, cargo shorts, lightweight cotton tee shirts and pants are fine too. How about a really cute baby hat, like a big floppy safari looking one? Hats are super useful in hot sunny climates.
You can even send a footed sleeper, since I still put my daughter to bed in them; it does get cooler at night and I want her to be snuggly warm.
I bet your friend is military like us!

Mitchell

All are really good answers. Of course, find out if they’re registered anywhere. A gift certificate to somewhere online like Amazon or Wal-Mart.com helps out in a pinch as well. If you give an online gift certificate, be sure they ship to Guam, as many places aren’t that smart and think its foreign.
And no, socks are not out of the question. Just cuz its hot doesn’t mean we don’t wear socks…just no wool sweaters!