My son refuses to take this tee off, which says a lot since he's picky about fabric. The cotton is genuinely soft and breathable, and it's held up through several washes without shrinking.
Hazel★★★★★
Bought this for our beach trip and my daughter wore it three days straight without a single complaint about being too hot. The 100% cotton really does breathe well in that humid coastal air, and it washed up fine after a sand-and-sunscreen mess.
Sebastian★★★★☆
The cotton is soft enough that my son wears it straight out of the wash without complaints. Only thing is it runs a touch small, so size up if your kid is between sizes.