LOS ANGELES — Michael Jackson's nephew and co-guardian to his three children testified on Thursday in a wrongful death lawsuit filed by the late pop star's family that the “Thriller” singer appeared happy at a family party about month before his death in 2009. “He was in a good mood, he was happy, making jokes,” T. J. Jackson, 34, the son of Jackson 5 member Tito Jackson, told jurors in a Los Angeles courtroom about the last time he saw the self-styled “King of Pop.” “We talked primarily about the children,” T. J. said. “I wanted to have more kids, so did he.” Jackson died about a month later at age 50 in Los Angeles from an overdose of surgical anesthetic propofol ahead of a run of 50 concerts in London. T. J. said he could not gauge Jackson's health at the party, a wedding anniversary for the singer's parents, Joe and Katherine Jackson. “I wasn't in the mentality to check him out,” T. J. said, adding that Jackson wore a suit. “He seemed happy, jolly.” Jackson's 83-year-old mother, Katherine, is suing privately held AEG Live, which was promoting Jackson's “This Is It” comeback concert series in London, for negligence in hiring Dr. Conrad Murray as his personal physician. When asked by an attorney for AEG Live if he believes Jackson was murdered, T. J. said, “I do.” — Reuters