You're asking in which I am assuming you want to say Happy Birthday to someone who is audibly impaired? In which case, you may need to be more specific as there are lots of different "languages" of sign language. Usually depending on which country you are from.
Sorry I didn't realise it was out of the American sign language folder. My apologies!
Yes
happy 18th
Grattis på födelsedagen
"Happy birthday" in Punjabi is spelled as "ਜਨਮ ਦਿਨ ਮੁਬਾਰਕ" (Janam din mubarak).
13
Birthday in Spanish is "cumpleaños" (singular or plural noun). Happy Birthday! = ¡Feliz cumpleaños!
Ra Whanau ki a Koe
Spell PATH, then show a path with both your hands
http://www.fineorient.com/images/productimages/happybirthday_main.jpg
¡Feliz Cumpleaños!
hair, dirt, pray, bird, data, tidy
It's translated "Feliz cumpleanos; eres maravilloso" in Spanish.
The same way you spell Happy Birthday in print only using cursive instead!