One of the best known early Nemos was the captain in Twenty Thousand Leagues under the Sea, while the more familiar modern one is the animated little orange fish in the Disney movie. Unusual name well worth considering. By the way, there is also a Shakespearean Nemo and one in Dickens's Bleak House. An enchanting early comic strip by Winsor McCay was called Little Nemo.

Very popular in Wales; this could make a nice middle name in honor of a Grandpa Glenn.

Honoring a male relative. Be bold and go with Glenn.