American actress Denise Richards, 38, has revealed that she feels sad about sending her daughter Sam, 5, to school.

Richards has two daughters with ex-husband Charlie Sheen, and they are also parents to Lola Rose, 4.

The actress said that the time had flown by very fast.

“It’s bittersweet,” People magazine quoted her as saying at the Much Love Animal Rescue’s third annual summer fundraiser Bow Wow WOW Howlywood! in Los Angeles.

“Sami starts kindergarten, which I cannot believe, in a couple of weeks. I’m so sad about it.

“I can’t believe how fast five years have gone. I’m very proud of her and very happy, but from here on out she’s in school,” she added