Send email when comment was answered

Hello,

I hope I’m in the right forum. I’m a websmaster and SEO specialist, and I created a blog for a client in the wordpress.com domain (as a subdomain).

Please suppose that a potential client enters a comment in the lawyers blog, and my client the lawyer answers the comment with some useful legal information, but my client wants to make sure that the potential client finds out that the lawyer answered the question in the blog.

So my question is that if there is a way in which the WordPress software automatically sends an email to the person who wrote the comment, so this person is aware that his question was answered in the forum.

Is it possible to do this? How?

I’ve been in “Settings -> Discussion” but I have not seen this option.

Can I still do this with a plug in or something?

I’ll really appreciate your help. Thanks,

Carlos M Chapa
OrelWeb.com