81 is just 18 Backwards.

THEREFORE...

81 Is the New 18

You know what ELSE?

"H"is for

 "B " Goes with

 and the "DAY" is for

 PUT IT ALL TOGETHER 

AND 

YOU GET

HAPPY B-DAY G-PA!

WE  L.O.V. E  YOU SO 

SO

SO

SO

SO

SO

SO

MUCH!

With all our love, 

Dan & Meems