After her husband died last year, she wrote a children’s book on grief. Now she’s charged with his murder.

Kouri Richins was arrested today in Utah, US, and is accused in charging documents of poisoning her husband with a lethal dose of fentanyl at their home in Kamas, a small mountain town near Park City.

Prosecutors allege that Richins called authorities in the middle of the night in March last year to report that her husband, Eric Richins, was “cold to the touch”. The mother of three told officers that she had made her husband a mixed vodka drink to celebrate him selling a home and then went to soothe one of their children to sleep. When she returned, she found her husband unresponsive and called 911.

A medical examiner later found five times the lethal dose of fentanyl in his system.

In addition to the murder charge, Richins also faces charges involving the alleged possession of GHB — a narcolepsy drug frequently used in recreational settings, including at dance clubs.

The charges, which are based on officers’ interactions with Richins that night and the account of an “unnamed acquaintance” who claims to have sold her the fentanyl, come two months after Richins appeared on local television to promote Are you with me? a picture book she wrote to help children cope after the death of a loved one.

For a segment entitled “Good Things Utah,” Richins called her husband’s death unexpected and described how it sent her and her three boys reeling. For children, she said, grieving was about “making sure that their spirit is always alive in your home”.

“It’s — you know — explaining to my kid just because he’s not present here with us physically, doesn’t mean his presence isn’t here with us,” she told the anchors, who commended her for being an amazing mother.

Richins’ attorney, Skye Lazaro, declined to comment on the charges.

- Sam Metz, AP