Do you think having your child write a hand-written thank you note is a good lesson or totally unnecessary?

some parents that i know have their children write hand written thank you notes to thank others for gifts they’ve gotten. I have other friends who never do this. As the recipient of the thank you notes, i think it’s charming but it does not matter to me if they do it or not. When i’m on the receiving end of a gift, i will send an email to my friends to thank them for gifts or for a good deed.

Do you think having children write a thank you note is a good lesson or totally unnecessary? As the mother of a three year old, i am coming into the era of birthday parties so i am wondering which path to take.