Katherine Jackson and Debbie Rowe
Robyn Beck-Pool/Getty; Pool Photographer/WireImage
In the wake of Michael Jackson's death
, Debbie Rowe, the singer's ex-wife and mother of his two eldest kids, has left multiple messages for the Jackson family in hopes of getting in touch – though she's been unsuccessful – a friend tells PEOPLE.
"We've been trying to reach them at different numbers," says Marc Schaffel, a former Jackson business associate who's close with Rowe. "But we don't know if who we've been leaving messages with have gotten the messages."
Rowe is the legal parent
of Prince Michael, 12, and Paris, 11, and can get custody of them if she chooses. Jackson's third child, Blanket, 7, was born to an unnamed surrogate.
But the children's grandmother, Katherine Jackson, was granted temporary guardianship on Monday after filing
a petition in Los Angeles Probate Court. In the 22-page document, Katherine claims the kids "have no relationship with their biological mother" and "have a long established relationship" with her since before Michael's death.
"In all fairness I wouldn't say they are avoiding her," Schaffel says, adding that Rowe usually contacts the family through Jackson's business office. "Our understanding, though, is that the Jackson family does want to have contact with Debbie."
Schaffel says there were "several reasons" why Rowe reached out, including wanting "to offer her input into a venue where they could have a public memorial."
"Debbie was absolutely devastated by Michael's death," he says. "They had an incredible bond and friendship even prior to the marriage...Debbie was a very good friend to Michael during all those years."
While Schaffel won't comment on whether Rowe has had contact with the kids the past few days, "Debbie understands it's a very difficult time for everybody involved, including the children," he says. "I think everybody involved would say they want to see the children have no more disruption in their life until their father has been put to rest."
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