My British kids don't know how to greet elders and it's my fault

Just came back from dropping my daughter Tolu at her friend's birthday party in South London. The birthday girl's grandmother was at the door, a Yoruba woman from Ibadan like me. Tolu walked straight past her, headphones on, mumbled 'hey' and went inside. I wanted to sink into the floor.

The grandmother just looked at me and said 'ah, these children o.' I smiled and apologised but inside I was screaming. When I was growing up in Ibadan, if I passed any elder without bending low and saying 'e ku le o' my mother would slap my backside before I reached the door. Now my own daughter cannot even lift her eyes from her phone to greet a woman old enough to be her grandmother. And whose fault is it? Mine. I am the one who let her grow up here without insisting. I am the one who got tired of fighting every morning about 'good morning ma.' I tell myself she is just British. But British children also greet. The white kids at her school say 'hello Mrs whatever' when they see me in the supermarket. My own flesh and blood cannot do it.

I called my mother in Ibadan tonight and she asked about the children. I told her they are fine. I did not tell her about the birthday party. She would cry. She would say I have lost my children to Oyinbo land. And maybe she is right. I am raising Nigerians who do not know how to be Nigerian. And the worst part is, I do not know how to fix it anymore. When did I become the person who just lets things slide?