It would be nice to mark their accounts as "temporarily grounded", as they haven't actually done anything 'bad'.
It would also be nice for the team to "add a nice word or two, maybe that this has legal reasons, and that they're welcome back when they're thirteen" (if that hasn't been done already).
For those who aren't aware, the terms and conditions stipulate that users should not be under 13. For some reason, this subject must have come to the fore, and these two users (maybe others) got nobbled. I'm guessing that it's because they self-identified as really being under 13 in other contexts than just their user profile, because there are plenty of users here who aren't suspended.
[It is mildly ironic that by suspending Nyuszika7h, SO also unwittingly disclosed his date of birth (he gets unsuspended on his 13th birthday :)]
(Some more retroactive irony in xiaohouzi79's suggestion to Benny in his penultimate paragraph here).