"Your birthday" can be translated as "Anata no [o]tanjoubi."
happy birthday
'(O)tanjoubi.'
Otanjou-bi Omedetou Gozaimasu!
'Otanjoubi WA itsu desu ka'.
'Otanjoubi WA raishuu desu.'
Yes it is.
You may say 'akemashite omedetou.'
You may say 'ojisan/jichan, otanjoubi omedetou,' written in Japanese: おじさん、お誕生日おめでとう
Japanese children.
The Japanese Happy Birthday song is sung the same way it is sung in English but in Japanese's translation. Even in most Japanese schools they also sing it in English version as well.
how to say "editor" in japanese
お誕生日おめでとう O tanjoubiomedetou