This is a sample apology letter for Broken Object.
Dear Person_Name …………………………
I came to know that my younger son has broken one window pane of your house with the cricket ball, while playing in the street. I apologize for the damage caused by my son. I request you to please send me the bill for the repairs.
Also, I assure you that such incidence will not take place again, as I have taken my son to task and scolded him to be very careful in future. If there is anything else I can do for you, please let me know.