Spears requested that Trawick join her court conservatorship a few months after the couple became engaged. They appeared in court together earlier this year, but the entertainer did not attend Wednesday's hearing.
She has been under a court-ordered conservatorship since February 2008, when her father stepped in to take control after she had been hospitalized twice and had a series of incidents involving erratic behavior.
Geraldine Wyle, an attorney for Jamie Spears, said after the hearing that her client was thrilled to have Trawick involved. Much of the hearing was closed to the public.
Trawick, who has served as Spears' agent, attended the hearing but did not comment after its conclusion.
At the request of attorneys handling the case, the judge did not consider the merits of whether to sell Spears' former home in the Hollywood Hills for more than $4 million. The sale can go forward without court approval.
The judge sealed several records related to the singer's health and settlements of lawsuits.
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