[Here focus on Sample leave application formats for school, college, university, office, factory, mill or company employees for attending a family function of any type. The function can be a party, marriage, dinner, family tour or any other type of function for that you want to leave. You can customize it according to your requirements.]
The Managing Director,
Sub: Leave Letter to Attend Family Function
With due respect, it is stated that I have to attend an important family function on (date). Therefore I will not be able to come to work. I cannot miss this function as all of my family attending and it is must for me to join.
I have shuffled my shift with my colleague and he will be handling my work for one day (Show your situation). All necessary filing has been done and documents have been archived on my desk. In case of any query, I will be able to provide assistance through the phone.
I will do a double shift next day to make up for my left-over work.
Thank you for understanding my position.