Jack Osbourne is reportedly having a "low-key" wedding in Hawaii this weekend.

The reality TV star and his fiance Lisa Stelly have reportedly tried to keep their upcoming nuptials a secret. A source revealed the couple, who have a five-month-old daughter together, have only just told family and friends about the ceremony.

"They just sent the invites out and are asking guests to sign non-disclosure agreements," a source revealed to the New York Post.

Jack was diagnosed with multiple sclerosis (MS) shortly after his daughter Pearl was born earlier this year. The son of rock star Ozzy Osbourne has said that having other priorities has helped him manage his condition. This includes planning his upcoming nuptials to Lisa.

"It's something great to focus on. Even when I was at the hospital, we were discussing the plans," Jack gushed in June. "It's going to be great."

The 26-year-old has previously spoken about how much he appreciates his partner Lisa's support with helping him deal with his condition. Sources have revealed that his life has changed for the better thanks to her supportive influence.

"Lisa makes sure he's healthy - eating right and exercising," a friend told Us Weekly magazine previously. "They love staying active as a family."