TERRE HAUTE — A local woman faces up to 30 years in prison if a judge accepts her guilty plea today to charges that she stabbed a couple while trying to kidnap their month-old son whom prosecutors said she wanted to pass off as her own. Judge Michael Lewis is scheduled to hear arguments during a 1:30 p.m. sentencing hearing for Stephanie Foster in Division 6. the 36-year-old Terre Haute woman pleaded guilty may 14 to a felony charge of armed robbery resulting in serious bodily injury in the June 2010 attack. in return, prosecutors agreed to drop charges of attempted murder and aggravated battery in the June 2010 attack. She also would be ordered to have no contact with the parents and child involved in the attack. Defense attorney Michael Wright declined to comment ahead of this afternoon’s hearing. he had told the judge last year he planned to offer an insanity defense for Foster. Foster has been in the Vigo County Jail since she was arrested at the couple’s home in the southern Vigo County community of Prairie Creek. Police said Foster suffered a miscarriage in 2009 and then spent months stuffing a pillow inside her clothes to feign pregnancy to her husband and others, forging birth certificates and attending baby showers as she plotted to kidnap a child. Foster targeted Ashley and Michael Speer after spotting a newspaper birth announcement of their son, police said. Ashley Speer let Foster in the family’s home after she asked to use the phone while the baby was sleeping in the living room, and Speer’s husband, who worked nights, was asleep in a bedroom. Foster allegedly dialed a random number, then hung up and left briefly before returning with what police described as a pellet gun from her car. Investigators said Foster pulled out a knife and began stabbing Ashley Speer as the new mother pleaded for Foster not to hurt her or the baby. Michael Speer heard the attack and was stabbed while subduing Foster, police said. Ashley Speer was hospitalized after the attack for stab wounds to her arms and back, while Michael Speer was treated for cuts to his arms and stomach. the child wasn’t injured.