"I love you, Mike, and I miss you," Janet wrote.
She signed the Tweet "Dunk," Michael's nickname for her.
Janet joined her family as her brother was interred at Forest Lawn Memorial Park & Mortuary in Glendale, Calif., on Thursday evening.
The service was attended by a host of Jackson's superstar friends, including Elizabeth Taylor.
Berry Gordy, Macaulay Culkin, Mila Kunis, Chris Tucker and Corey Feldman were among the nearly 200 who attended Jackson's service.
A rep for the family confirmed he was laid to rest at 9:43 PM.
Michael Jackson died on June 25 at the age of 50. He is survived by his three children – Prince Michael I, Paris and Prince Michael II, aka Blanket.
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