Demi Lovato slammed Twitter haters who bullied her sister, Madison De La Garza. According to a report from J-14, the "Cool for the Summer" singer even tweeted her fans to help her defend her younger sibling.

The former Disney star's little sister revealed in a recent interview with Seventeen magazine about how she was attacked in the past by cyber bullies. Aside from starring in the hit TV series "Desperate Housewives" years ago, Madison De La Garza's life has been relatively quiet, thus her celebrity sibling's tendency to be very protective.

"Last year I got a ton of negative comments after I posted a Vine on Twitter where I was cooking with Demi," Madison De La Garza narrated.

"People made fun of me, saying I had a hunchback."

She then recalled how Demi Lovato called out the Twitter bullies to defend her. "She freaked and direct-messaged people to yell at them," the teen shared. "She even tweeted at her followers to stand up for me."

Apart from Demi Lovato's Twitter war with their haters, Madison De La Garza said that the singer-actress is very kind-hearted.

"When Demi is home, our relationship is just like any sisters'," she said.

"We talk about anything and everything. I know I can trust her with it all."

Entertainment Tonight Online previously reported about how Demi Lovato said that she wants to be a role model for her sister and other young people.

The girlfriend of Wilmer Valderrama even confessed about how she wants to be a good example because she used to look up to bad influences when she was a teenager.

"I had a lot of people that I looked up to when I was younger that weren't the best role models," Demi Lovato admitted.

"So for me, it's a responsibility to hold myself accountable and to be that inspiration for young girls and even people who are older than me."

"I have a little sister and I wouldn't want her looking up to other people who don't necessarily use their voices for good," she added.