A couple of years ago their mother gave birth to twins, a boy and girl, who were premature. They didn't survive, and we were all heartbroken. Naturally we're thrilled that this little guy was born full term and appears healthy, even robust.
Welcome, little one.
Update: Incidentally, for more details about our other recent arrival, grandson Elmer Kai Barrientos, check out my daughter Noelle's blog.