Amber Portwood Denied! Judge Refuses to Let Her Participate in Teen Mom Reunion in NYC

"He thinks it will interfere with her program," the reality star's mom says; Gary Shirley and daughter Leah will be attending

The show must go on, even without Amber Portwood.

The casts of Teen Mom and Teen Mom 2 are all heading to New York this weekend to participate in a reunion special, with one notable exception.

Why will Portwood be MIA?

Amber's mom, Tonya, tells E! News that the judge overseeing her daughter's probation denied Amber permission to leave Anderson, Ind., to participate in the MTV taping.

"He thinks it will interfere with her program," says Tonya.

Despite the setback, Amber exclusively tells us that it's not the end of the world.

"I'm happy...just stressed, but I'm happy," says Portwood, who has been fitted with an ankle-monitor tracking device.

Last week, she was released from the Madison County correctional facility where she' had been since December. Portwood is staying with her maternal grandparents while she attends eight months of court-mandated outpatient rehab at Sister 2 Sister Ministries. If she violates her strict probation in any way, she faces a maximum of five years in prison on her felony drug-possession charge.

But even though Amber herself won't be present at the massive Teen Mom reunion, she will likely be a topic of convesation. Her baby daddy, Gary Shirley, posted on Facebook that he and their 3-year-old daughter, Leah, are flying to New York Saturday to participate in the special.