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Federal investigators have cleared two doctors in California and Texas of any wrongdoing in the death of actor Heath Ledger.

The Drug Enforcement Agency interviewed the doctors earlier this week about prescriptions found in Ledger’s apartment and determined they did not prescribe him the two most powerful drugs – Oxycontin and Vicodin, the New York Post reports. The doctors did meet with Ledger but prescribed him other medications, according to investigators.

Ledger, 28, died on Jan. 22 in his Manhattan apartment from an accidental overdose of prescription drugs. Soon after the medical examiner released his cause of death, the DEA issued subpoenas to try to determine if there were medical conditions attached to all the drugs found in his apartment. That investigation is still ongoing.

Besides Oxycodone and Vicodin (also known as Hydrocodone), autopsy results also showed that Ledger’s system contained Diazepam (commonly called Valium), as well as Temazepam, which treats anxiety or sleeplessness; Alprazolam (also known as Xanax); and Doxylamine, a sedating antihistamine often used as a sleeping aid.

Michelle Williams – Ledger’s former girlfriend and mother of his 2-year-old daughter, Matilda – joined Ledger’s family and hundreds of mourners Feb. 9 at a memorial in Australia for the actor. On Jan. 26, a private memorial in Los Angeles was held for close friends and family.

Britney Spears is spending more quality time with her sons.

Preston, 2, and Jayden, 17 months, spent more time at their mother’s house on Wednesday morning – the third visit Spears has had with her children since lawyers for the singer and her ex-husband Kevin Federline reached a visitation agreement on Feb. 22.

Spears’s recent visits with her boys have been full of hugs and affection. “Kids this age are amazingly resilient, and the very close bond that Britney has with her children is apparent,” a source says.

On Saturday, Spears reunited with her sons for the first time since she was hospitalized at Cedars-Sinai Medical Center Jan. 3. She also had another visit with them Monday.

According to the source, Spears’s father, Jamie, and psychiatrist Dr. Lee Sadja have been monitoring the visits between the boys and Spears, who has had two stints in the hospital this year. Sadja began treating the singer during her most recent hospitalization at the UCLA Medical Center psych ward.

Angelina Jolie has penned an op-ed article urging the United States to help Iraqi refugees who have been displaced by the war. In The Washington Post piece titled, “Staying to Help in Iraq,” the actress and goodwill ambassador for the United Nations High Commissioner for Refugees says American support is key to addressing the humanitarian crisis, which has displaced more than 4 million people. Of the 2 million refugees within the country, 58 percent are under 12 years old, according to Jolie. The 32-year-old actress, who recently visited the war-torn country, writes, “What we cannot afford, in my view, is to squander the progress that has been made. In fact, we should step up our financial and material assistance.”