It is known that Google celebrates many occasions from considered engine logo change, to add this feature to the user by making the Google for any user that is logged into his account agreed on to Google on his birthday, so will Google Google logo change slogan expresses celebrate the birthday of the user, the user only needs to enter account information on his birthday in at Google, and you can go from here.

I think that this is distinct from Google for user interaction with birthday celebration.

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