Lindsay Lohan and her siblings are being harassed by Britney Spears' ex-manager, Sam Lutfi, according to a source close to the situation, RadarOnline.com is exclusively reporting.

Lutfi was Spears' controversial former manager at the height of her epic public meltdown when she lost custody of her children, Sean Preston and Jayden James to her ex-husband, Kevin Federline. Spears was twice committed to a hospital involuntarily while Lutfi was a major player in her life. Brit's dad, Jamie Spears, got conservatorship of her and obtained a restraining order prohibiting Lutfi from having any contact with her.

Numerous text messages and emails have been sent from Lutfi to LiLo and her siblings in recent weeks. "Sam is desperate to be in Lindsay's life and is telling anyone that will listen that he is helping with the actresses' comeback. This is absolutely false. Lindsay has a team in place consisting of an agent, manager and publicist. She doesn't want nor need Lutfi in any capacity. Sam has been texting and emailing Lindsay's siblings as well. Lindsay and her sister and brothers aren't responding to any communication from Sam," a source close to the situation tells us.