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Kristen Bell told her children when she tried magic mushrooms for her birthday.

The 'Forgetting Sarah Marshall' actress - who has daughters Lincoln, nine, and Delta, seven, with husband Dax Shepard - has recalled celebrating her 40th birthday by taking hallucinogenics, and she decided to be honest with her kids.

Speaking on 'Jimmy Kimmel Live!', she said: "We've always been really honest with our kids, and I had never really done any drugs and I wanted to try mushrooms for my 40th birthday.

"So my husband got them for me and I tried it. And we told our kids about it."

However, things backfired somewhat when one of the girls told their grandmother, who is more conversative than Kristen.

The 42-year-old star added: "I overheard my daughter taking to my mom, to grandma, going, 'So anyway, so mom really wanted to try mushrooms, so'.

"And I just walked by and I was like, 'Uh-oh, uh-oh, uh-oh.' For some reason I'm more worried about telling my mom that than telling my daughter."

Kristen admitted there was no chance her children misunderstood the kind of mushrooms she decided to partake in.

She explained: "Their dad is in recovery, so he's really honest about what alcohol does to your body, how it makes you feel funny and impairs things. What drugs do your body and why most drugs are illegal and all that."

And she has no problem with him bringing that level of honesty to their parenting.

She said: "He has committed to being very involved in our kids' lives and very involved in our marriage. He's a real go-getter. I got no complaints."

Meanwhile, Kristen recently revealed how her children help keep her grounded when she gets home from a day at work.

She joked: "The amount of insults that they can hurl at me in a very short period of time. it really brings me back down to earth. I come home from a day like today - which is pretty elegant and fancy - and we're talking about work and I've had my makeup but they will just they'll pull the rug out from under you so quickly.

"My autobiography title would be 'My Kids Keep Me Grounded!'"