I highly doubt that Amma would have had children outside of marriage. She is a practicing Catholic from what we see, often attending church, and originates from a religious milieu. Rather, perhaps she was divorced, or, simply estranged from her husband while staying married. (That is the case with Narendra Modi, the current prime minister of India, who never got divorced, but separated very early on after the marriage, from which no children were borne. Maybe now he is divorced, but that is thirty or forty years after the separation. Ok, he is Hindu, and Tiffany's family is Catholic, but both religious with Indian origins.)
Anyway, Tiffany had mentioned in some earlier video that she was born in France, but never explained how they ended up in the UK. However, Tiffany's last name is 'Maurice-Christy'. Maurice was her father's first name, and is a French name. Tiffany most likely does not know French and the family must have left France when she was small, as Tiffany pronouned Maurice like 'Morris', and that is not how it is pronounced. Reunion Island, a French territory in the Indian Ocean near Madagascar, has a lot of Tamil people--some Hindu but a lot of them Christian. I had the chance to visit Reunion Island in June of this year. The people there look like Tiffany. Close to Reunion Island is 'Ile Maurice', which translates to 'Maurice Island' ( I have not been there.) There, the people speak both English and French. Schools are in English there, as it was a British territory. Perhaps Tiffany's dad came from Ile Maurice, immigrated to Reunion Island (France), came to mainland France from there, but preferred to settle in the UK. It would be fascinating if Tiffany would talk about her origins, but she has not.
Yes, she says she is of Sri Lankan origin, but Reunion Island and Ile Maurice were originally populated by people from India and Sri Lanka. Maybe she has nothing to do with either Reunion Island or Ile Maurice, but I just mentioned it because she said she was born in France, and because I visited Reunion Island recently, I thought of Tiffany and her possible origins.