Updated

Rumer Willis, the eldest daughter of Demi Moore and Bruce Willis is one proud big sister reports People magazine. She opened up about her younger sister Tallulah who is in recovery after seeking treatment for various issues.

"I've actually been so impressed and blown away by her strength and her openness and willingness," Willis, 26, told the magazine at an event in Beverly Hills. "Not only to move past things but also to share herself with other people."

Tallulah, 20, finished six weeks of treatment in September. The fashion blogger revealed her struggles with an eating disorder and body dysmorphia in a video interview.

Rumer who spent most of her teenage years in Idaho attributes some of her younger sister’s problems to have grown up in Los Angeles.

Of her sisters ( her other sister Scout Willis is 23), Rumer says, "They kind of grew up more here, so in a way, it's interesting because they’ve had such a different experience than I had. They moved out to L.A. when they were younger, so they were kind of exposed to everything a lot more."

A source told People that Tallulah was “adversely affected” by her parents’ divorce in 2000.

"When you grow up like we do, everyone has an opinion of you. Everyone wants to put you in a particular box," explains Rumer. "If you get photographed the wrong way or you're at a party, it doesn't matter if you're drinking or not, you know, it's whatever the perception is. So if you allow yourself to find your value in other people's perceptions of you, then you will never be happy, whether it's good or bad."