WIBTA for not letting my MIL tell our kid that the tooth fairy is real?

A couple expecting their first child is already clashing with grandma-to-be over one of childhood’s most beloved traditions: the Tooth Fairy. At 20 weeks pregnant, the parents have decided they never want to lie to their future kids about magical figures like Santa, the Easter Bunny, or the Tooth Fairy — even if they’ll still celebrate all the holidays and tooth-losing milestones with full joy and excitement.

But the husband’s mother, a passionate dental hygienist who’s written an unpublished book about the Tooth Fairy and even crafts tiny doors for her young patients, is deeply invested in the myth. The parents worry she’ll insist on telling their child it’s real — and they’re not sure they can allow it. Is standing firm on their “no lies” rule worth the family tension, or are they overthinking a conflict that’s years away?

‘WIBTA for not letting my MIL tell our kid that the tooth fairy is real?’

The parents explained their clear stance on parenting from the start:

Everything felt settled — until they thought about the MIL:

This dilemma highlights a classic parenting tension: the desire to raise children with radical honesty versus the cultural value of playful fantasy and imagination in early childhood. The parents’ commitment to never lying is rooted in a wish for trust and authenticity, but many child development experts note that make-believe stories like the Tooth Fairy serve important psychological purposes — they spark wonder, encourage positive habits (like tooth-brushing), and help children process the line between reality and fantasy.

Dr. Alison Gopnik, a renowned developmental psychologist and author of The Philosophical Baby, argues that pretend play and magical thinking are essential for cognitive growth. In her research, she explains that children naturally distinguish between fantasy and reality by age 3–4, and participating in shared cultural myths actually strengthens social bonds and emotional development rather than eroding trust. Banning these stories outright can sometimes make children feel left out or overly serious among peers.

A common compromise many families use is framing the Tooth Fairy (and similar figures) as “fun pretend” or “special family stories” — especially when grandparents are involved. This allows Grandma to play her enthusiastic role without parents endorsing it as literal truth. Parents can gently explain to the child: “Some people love to pretend the Tooth Fairy is real, and that’s a sweet game we can play with Grandma.” This preserves family harmony, lets the child enjoy the magic, and still aligns with the parents’ core value of honesty.

Ultimately, since the child isn’t even born yet (and tooth-losing is 5–7 years away), the situation offers plenty of time to discuss boundaries lovingly with the MIL. The key is flexibility: rigid “no lies ever” rules often soften once real parenting begins, and allowing a bit of shared fantasy doesn’t have to mean betrayal — it can simply be part of the joy of childhood.

Here’s the input from the Reddit crowd:

The online crowd was divided, with strong opinions on both sides of the honesty-vs-magic debate:

Many commenters felt the parents were being overly rigid and urged them to let kids have the fun of imagination:

Others supported the parents’ right to set boundaries and praised their commitment to honesty:

A few pointed out the practical side — kids will hear the stories anyway:

This early parenting debate shows how even the sweetest traditions can spark deep family conversations about values, trust, and imagination. The parents have every right to guide their child’s worldview, but childhood magic is fleeting — and many adults look back fondly on those moments of wonder, even after discovering the truth. Finding a middle ground that respects both the parents’ principles and Grandma’s passion could keep everyone happy for years to come.

What do you think — would you hold the line on no magical lies, or allow some Tooth Fairy play-pretend for the joy of it? Share your take in the comments!