I can write 之 whose birthday is it

Ah Gong's birthday was coming so we picked up a postcard with a beautiful birthday cake in front and wanteda post it to him.

the address, "birthday" and date were written by Mummy.
The rest are written by me with a little help from Mummy.
My favourite alphabet is "H" cos that's my name!
actually I don't really like to write at the moment cos my pencil grab is still rather weak.
I tend give up after awhile.

mummy told me that the postman will pick up the postcard and send to ah gong after I slip it into the mailbox.

the next day, we went for ah gong's birthday dinner and I asked him, "Where's our postcard?"
argh... he has not open the letterbox yet.
so we went to open it together and there! is my postcard.
I was so happy to see it!
and told Mummy, "the postman send it to ah gong right?"