Terry Chay

<a href="http://terrychay.com/wordpress-plugins/blog-birthday" rel="nofollow ugc">Plugin Homepage</a>
Inspired by @TwBirthday on Twitter, this shows a simple message in the admin panel on 
their blog birthday.
“Happy 3rd Blogger Birthday! You’ve been around since 11 August 2008.”
“Happy 7th Blog Birthday! The first post on this blog was on 19 November 2004.”
“Happy 1st Blog Birthday! This blog was first registered on 23 July 2010.”
Caveats: 
– Old WordPress admin accounts have a registration date of 0000-00-00 and never have a 
 blogger birthday. 
– Blog registration starts when you turn on WordPress multisite. If you did this, the 
 date may be off. 
– First post assumes that there a post_id=1 and uses the date off that.
<h3>Future Features</h3>
<ul>
<li>Add ability to change the blogger birthday if blank</li>
<li>Add ability to change the blog registration date if first post is different.</li>
<li>4567890012345678900123456789001234567890012345678900123456789001234567890012345678900</li>
</ul>

Blog Birthday

Show a user a notification on their blog birthday.

Prashant Singh

Pooja Sahgal

BP Birthday Greetings plugin will send a birthday greeting notification to members. You just need to create a DOB field and have to map in the plugin settings, that you can find under options tab of BuddyPress settings.
We have one widget called BuddyPress Birthdays that you can use in sidebars to display the list of member birthdays and can wish them as well using private message functionality of BuddyPress. One shortcode [ps_birthday_list] is also added which can be used to list birthdays as well.

BP Birthday Greetings

BP Birthday Greetings will send birthday greeting notification to the member from community.

Blog Birthday vs BP Birthday Greetings