Is this mum ‘ruining Christmas’ by telling her child the truth?

Many are against her.

A new mother has taken to Mumsnet after her mother-in-law said she was ruining Christmas by wanting to tell her child that Santa Claus isn't real. Her mother-in-law called her awful and selfish, so she doesn't know what to do now.

"Mil was saying it won't be long until dc will believe in santa-claus (dc is only 22 months so surely it would be next Christmas not the upcoming Christmas). I mentioned we were thinking of not doing the whole santa-claus thing and telling him the truth. Mil said how awful I was, and I will be ruining Christmas for my dc and that I'm a very selfish women. "AIBU to think that's a over reaction and it won't ruin Christmas. Any of you not do the whole santa-claus thing for Christmas?"

The child is still young so she has time to decide, but many users on the site said that she was taking the joy of Christmas away from her kid. There's also the big problem of him telling his peers. One said:

"It has not harmed any child believing in Santa and I don't think it's fair on your little one being the only one especially when they start school to not believe in Santa. Imagine if they started telling his friends that Santa isn't real and the friends say he does and it causes conflict in the friendship, because at a young age I'm sure it would. "What harm is there in letting them believe in Santa?"

While another wrote:

"Although ruining Christmas is a bit extreme I do think it would take away some of the magic of it in the early years. "If you tell him the truth from an early age you better do some serious priming to make sure he doesn’t spoil it for his peers."

Do you think this mum is being fair?