I don't see a strong pattern. There are others named after female first names that aren't particularly popular (most, really), though the set of popular languages is small enough that it's not clear there's enough data to draw any conclusions.

Apart from Ada, which is probably the most popular language in the category, there are two named Alice (http://www.alice.org/, http://www.ps.uni-saarland.de/alice/), and others named Claire (http://www.claire-language.com/), Mary (http://en.wikipedia.org/wiki/Mary_(programming_language)), and Miranda (http://miranda.org.uk/). If you allow ancient Greek names, there's also Io (http://iolanguage.com/) and Ioke (http://ioke.org/).