Pop princess Britney Spears denied today accusations she yelled at a 13-year old girl on the set of her sister Jamie Lynn's TV show, insisting she only gave the child a "sisterly talking to".

It appears her sister didn't get along with co-star, Alexa Nikolas, so Britney rushed to Zoey 101 set last week to defend Jamie Lynn. Acting like a 'real' big sister, the singer "proceeded to scream that Alexa was an 'evil little girl,' and that she had better watch herself or she 'will never work in this town again!'"

A spokeswoman for Spears says, "Jamie Lynn and another girl on set were having problems, as 13-year-olds do.

"Britney did have words with the girl, but felt she was sticking up for her sister. She did not yell by any means, she just gave the girl a sisterly talking to and wondered why they just couldn't all get along."

But the on-set source says, "Alexa was in tears. She was sobbing and totally upset - it was totally uncalled for.

"While Jamie Lynn is the star, Alexa still works there. And the fight was a petty, 13-year-old thing between Alexa and Jamie Lynn, who is becoming a real pest. Britney should have stayed out of it."