I can't see it's his burthday on his profile.

I know that racehorses officially are a year older on the first of the year, no matter when they were born.

So, given the eidence at hand, I can't exactly accept that it's his birthday, even if Vincent is a Thinder Horse.

But I'll go ahead and with

HAPPY BITHDAY TO YOU, VINCENT, THUNDER GOD

anyway.