Hes had 45 birthdays of his own, but were not quite sure if Jim Parsons knows how they work yet.
Because the Big Bang Theory actor just accidentally sabotaged co-star Kaley Cuocos 33rd by spoiling her big surprise all over Instagram.
If hed been lucky, Kaley might not have been one of his 6.5million Instagram followers to come across his picture of the delicious buttercream birthday cake waiting for her on the TBBT set.
That is, if he hadnt specifically tagged her in the post.
Almost time @kaleycuoco… he wrote, followed by Shhhhh! with not a hint of subtly.
Low and behold, less than five minutes later, he snapped the unimpressed birthday girl holding up her phone with the post on her feed.
Oops @kaleycuoco, he teased.
It seems Penny is not immune from a Sheldon-style blunder, even when the cameras arent rolling.
The cast are thought to still be piecing together the 12th and final series of TBBT, which is expected to come to an almighty end with episode 24 in May 2019.
The 24th episode will not be filmed until April 30 next year, according to Raj actor Kunal Nayyar.
Episodes from the 12th series are currently airing in the UK and US but the show is expected to take a break before returning to screens in 2019.
The gang have now been filming together for 12 years and Jim has already said that he will miss it more than he can say.
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