Answer:
Apology letter for not attending a friend's birthday party.
Explanation:
ABC Apartments
New Delhi
My dear Sushma,
First, Happy Birthday once again.
I know you had invited me and had expected me to be there last night. But due to the sudden hospitalization of my father, I couldn't attend the party. And I am extremely sorry for missing your special day.
I hope you can understand my condition. I will make sure I make up to you. Let my father get well first and then I will be there to make up for my absence in any way possible.
I'm really sorry about missing the party. Hope you will forgive me.
Take care and I will see you soon.
Your loving friend
Ruchi.