Mariska Hargitay and Ice-T have been costars and friends for a very long time. Ice-T has played Detective Fin Tutuola on Law & Order: SVU since Season 2, which premiered in the year 2000. So, this year is the 20th year that he and Hargitay have been onscreen together.
It's well-known that the cast of Law & Order: SVU is just as close in real life as they are on the show. So, it's no surprise that Hargitay wished her costar and friend a happy birthday in the cutest way possible.