Was this sand dollar the boy found still alive?
Most likely....................
Likely not. They look totally different when they’re alive. The following is a great video about them.
https://thekidshouldseethis.com/post/what-sand-dollars-really-look-like
Sand dollars are gray when you find them alive, or some lighter variation of that as they die. They are not white that I’ve ever seen. It is very hard to find fully intact sand dollars that are that white. I’m a little skeptical that he found a live sand dollar and wonder if maybe he bleached it to get it that white. I’ve seen lots of people do that.