When Is National Sister Day?

The internet history of Sister Day

3rd of August is National Sister Day

  First detected on the 10th of April 2015

  36,698 tweets

sister children siblings brother

Is It Sister Day Today?

It's Sister day on the 3rd of August.

The most recent detection of references to Sister Day was 4 months ago.

There were many celebrations relating to national holdiays written about on social media that our algorithms picked up on the 3rd of August. In total we detected 142 total unique days being shared such as Sister Day which had 7,632 people talking about it, or Watermelon Day having 7,192 tweets.


How Is The Date For Sister Day Calculated?

The day shown for 'National Sister Day' is based off how much chitter-chatter and buzz there was on Aug. 3, 2015 across social media making references to 'Sister Day'. Our algorithms examine all of the references to National Days across social media and updates whatnationaldayisit.com hourly, with our homepage displaying the current national day, including others such as: Sisters, Girlfriend or Liberation Day. This crowdsourcing of data method to assess the National Sister Day date is used as opposed to being connected with any Government sacntioned lists :D Hurrah for democracy by concensus!


I'd Like To Promote National Sister Day

We've put together the following resources full of nifty tips on how to increase the reach of Sister Day. The resources include: graphs, badges, and resources on what steps to take to boost Sister Day's visibility.

Can I Register Sister Day?

We don't have an international authority or governmental remit to declare any officially celebrated "national Sister day". We only aim to programatically reflect what 'National Day' it is based of what The Internet Says It Is. We believe this is much more fun as it reflects the nature of how the most amusing / interesting national days are often created organically and grow based off popular social trends and sharing, as such we don't add new days to our database unless they are organically observed on social media.



Is it National Sister Day Everywhere?

Yes? No.. Sort of | Maybe ¯\_(ツ)_/¯

What's really intersting is how whilst some National Days like National Daughters Day are seemingly celebrated internationally irrespective of geography, some very popular days (That often become the No. 1 National Day on our homepage) are in fact locally very specific and are offical holidays celebrated on a Country's national calendar. Take National Rambutan Day for instance, Rambutan is a popular Souteast Asian fruit and not seen so much in the UK, Europe or the USA. Some regionally specific trends subsequently become immensely popular internationally and worldwide, partly fuelled by widely shared 'National Days', National Pabebe Wave Day being one such example.


We're now tracking the sentiment around every mention of Sister day to show how people feel about Sister. See if people like Sister here.
We're detecting how Sister affects other things more widely than just being a celebrated day. See how Sister affects company share prices.


Hang On, It Was National Sister Day Already This Year..!?

Yes, this is strangely enough entirely possible. The date shown for National Sister Day can change, if for instance several hundred people tweeted about Sister Day in early April, then in May a few thousand people tweeted about Sister day, then the date shown for National Sister Day, could come up twice :D

We have also detected mentions of Sister day on;



Get The Badge

National Sister Day

It's Sister Day
On August 3rd


WhatNationalDayIsIt's Daily Day Widget

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<iframe src="https://whatnationaldayisit.com/today_badge/"  height = "300px"    frameborder="0" scrolling="no"<  /iframe>


National Sister Day, on the 3rd of August

Other Days

National Sibling Day
National Siblings Day
National Ex Day
National Kiss Day
National Hug Day
National Youth Day
National Concert Day
National Sister Day
National Sisters Day
National Hugging Day
National Hat Day
National Brothers Day
National Teacher Day
National Friends Day
National Teachers Day
National Bootie Day
National Close-Friend Day
National Light-Skin Day
National Brother Day


For any media or sponsorship queries, please contact info@whatnationaldayisit.com
For people who wish to promote National Sister Day, we've put together the following resources.
See also: How does Sister affect the share price of Apple, Facebook, Microsoft?
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