Answer:
Dear Gramma,
It's been so long since I've last seen you! My birthday is coming up soon and even though you live far away, I'm hoping you can make it. I have some amazing news for you. Mum got a new job! She is now an Information Security Analyst and get paids very well! She already took us out for ice ceam 2 times this week! She is very happy and seeing her happy just makes my day. Please write back when you can
I miss you,
(name here)
P.S: Tell grandpa I said happy birthday!!