Dear {Recipient},

I'm sorry your child got head lice after coming over to our house and playing with my {son/daughter} last {day of the week}. I wasn't even aware that there was a problem until I received your {text message/phone call}. I immediately checked my {son/daughter}'s head, and sure enough, I found some lice.

I apologize for the inconvenience this has caused you and your family. If I may, I would like to recommend the over-the-counter treatment called {name of treatment}, which you can get at {drugstore}.
I hope your child gets better and that our kids can play together again soon!

Sincerely,

{Your Name}

Dear [Name],

I am writing to apologize for the infestation that has occurred in your home. I understand how frustrating and upsetting this must be for you and your family, and I want to express my sincerest apologies for the inconvenience that this has caused.

I take full responsibility for the infestation, and I am doing everything I can to rectify the situation. I have already contacted a professional exterminator to come to your home and take care of the infestation. They will be arriving within the next few days to take care of the problem.

In the meantime, I understand that this is an incredibly stressful situation, and I am doing everything I can to make it easier for you. I have already provided you with a temporary residence while the exterminator takes care of the infestation, and I am also providing you with a full refund for any expenses you have incurred due to the infestation.

I want to assure you that I take this situation very seriously, and I am doing everything I can to make sure that it is taken care of as quickly and efficiently as possible. I understand that this is an incredibly difficult situation, and I want to make sure that you are taken care of during this time.

Once again, I apologize for the infestation and the inconvenience that it has caused. I am doing everything I can to make sure that the problem is taken care of as quickly as possible, and I am here to help in any way that I can.

Sincerely,

[Your Name]