Kasem's second wife Jean Kasem currently has control, but has denied Julie, 38, Kerri, 41, and Mike, 40, from seeing their 81-year-old father, who has advanced Parkinson's disease, for the past three months, the children say. The trio filed the request Monday in Los Angeles Superior Court.
The children, along with more than a dozen friends of the American Top 40 host, staged a protest outside of his home on Oct. 1, but Jean refused to give in.
Julie, Kerri and Mike insist the issue isn't over money because they're all "self-sufficient and are not listed in his will anyway," according to a previous statement from Kerri.
"All we want is to see our dad," she continued. "It's as simple as that."
"When he was healthy, our dad used to talk to us all the time. We're his joy," Kerri previously told the magazine. "Now we've been cut off from him. The same goes for many of his friends. We just want to know that our dad is okay."