Thank you for the outstanding follow-up. As you noted, the youngest child of James Washington Allen was Wade Dixon Allen. My grandfather knew his Uncle Wade fairly well. So...like, you mentioned, even though J. W. Allen was born in the 1840's, this isn't ancient history.
What I'm most curious about at this point, is the exact arrival date of these Allens in Texas. I'd love to discover that they showed up in the Republic of Texas days, but I think they most likely showed up around 1850. Since James Washington Allen and his parents arrived in Texas, his direct line, including me and my family, have lived on the Texas Gulf Coast, or near it.