Appeal from the Circuit Court of the 10th Judicial Circuit, Peoria County, Illinois, No. 01-CF-344 Honorable Michael E. Brandt, Judge, Presiding.
 The opinion of the court was delivered by: Presiding Justice Holdridge
 A jury found the defendant, Ronald L. Wells, guilty of first degree (felony) murder (720 ILCS 5/9--1(a)(3) (West 2000)) and concealment of a homicidal death (720 ILCS 5/9--3.1(a) (West 2000)). The felony murder conviction was based on robbery. The defendant was sentenced to concurrent prison terms of natural life and five years, respectively. On appeal, the defendant is challenging only his murder conviction and sentence. He argues that (1) the State failed to prove beyond a reasonable doubt that he committed the robbery upon which his felony murder conviction was based; (2) he was not eligible to receive a natural life sentence; (3) his trial counsel was ineffective by failing to fully develop a self-defense theory; and (4) the trial court erred by failing to instruct the jury on self-defense, second degree murder, or attempted murder. We affirm.
 The events in question took place in Peoria. On March 15, 2001, the victim, Jamie Weyrick, and the defendant drove in Weyrick's car to find someone from whom Weyrick could buy marijuana. The defendant located a person named "Curtis" who said he would sell marijuana to Weyrick for $200. Weyrick gave $200 to Curtis, who left with Weyrick's money and did not return. Weyrick told the defendant that he held the defendant responsible for losing his $200 and expected the defendant to reimburse him for the loss.
 The defendant told Weyrick that he did not have $200 to repay Weyrick, but he could make some phone calls to get the money. Weyrick and the defendant then drove toward the defendant's home in Weyrick's car.
 Weyrick's girlfriend, Patricia Lane, testified at trial. On cross-examination, defense counsel asked Lane about Weyrick's affiliation with the Gangster Disciples. The prosecutor objected on relevance grounds. After the defense counsel's offer of proof, the trial judge sustained the State's objection.
 The defendant gave two videotaped confessions to the police. In the first confession, the defendant stated that he killed Weyrick in someone else's garage. The defendant said that Weyrick threatened the defendant by showing him a gun.
 In the second confession, the defendant admitted killing Weyrick in the defendant's home. The defendant said Weyrick told the defendant that he had a gun, but did not show the defendant the gun. The defendant stated that Weyrick had a reputation for having a gun and the defendant thought that Weyrick was armed with a gun. However, the defendant said that Weyrick, in fact, did not have a gun on his person.
 The defendant's wife, Angela Wells, agreed to testify in the defendant's trial after pleading guilty to Weyrick's murder. Angela stated that Weyrick and the defendant entered the house. The defendant then had a conversation with Angela in the bathroom. After the conversation, Angela went into the living room with the children and began to cry. In his second confession, the defendant stated that Angela and the children did not arrive at the home until after he killed Weyrick.
 According to both Angela's testimony and the defendant's second confession, the defendant and Weyrick went upstairs to the kitchen. In his second confession, the defendant said that he stabbed Weyrick in the back with a knife in the kitchen. The defendant said that Weyrick turned and fought with the defendant, who stabbed Weyrick multiple times in the neck and chest. The defendant left Weyrick on the kitchen floor after the defendant thought Weyrick was dead. He said that he left the knife next to Weyrick. The defendant stated that he went downstairs, but then returned to the kitchen. He alleged that when he returned to the kitchen, Weyrick attacked him with the knife. The defendant said that he got the knife away from Weyrick and stabbed Weyrick several more times.
 The defendant's son, Dustin Gaston, also testified at trial. Both Angela and Gaston testified that they heard the defendant and Weyrick fighting upstairs. They heard the fight continue down the stairs into the front room. Angela and Gaston both stated that they heard Weyrick plead for his life. Angela said that Weyrick told the defendant, "I gave you all I got."
 In the defendant's second confession, the defendant said that after he stabbed Weyrick several more times in the front room, Weyrick fell to the floor in a pool of blood. According to Angela and the defendant's second confession, Angela and the defendant wrapped Weyrick in a blanket, carried him to the basement, and put him in an unplugged, empty freezer.
 In the defendant's second confession, he stated that he took $400 from Weyrick's wallet. He said that he took Weyrick's ATM card out of the wallet along with a piece of paper with the PIN number for the ATM card. The defendant then threw the wallet in the trash. However, Angela testified that it was she who took Weyrick's ATM card and PIN number from the wallet. Angela stated that she also took $1,000 from Weyrick's wallet. Angela said that she later used Weyrick's ATM card and PIN number to withdraw $10 from Weyrick's credit union account.
 In his second confession, the defendant stated that he took Weyrick's gold "nugget" ring and silver necklace. The defendant said that he sold the necklace and pawned the ring. A pawn shop owner testified that the defendant pawned the ring, but later returned and redeemed it.
 Angela testified that the defendant cleaned the blood off himself, changed clothes, left the home, and did not return for several hours. According to Angela and Gaston, the defendant drove away in Weyrick's car. According to both of the defendant's confessions, the defendant paid a third party $200 to dispose of Weyrick's car. After Weyrick's disappearance, Lane located Weyrick's car parked in a neighborhood far from Weyrick's home. Lane then notified the police about the location of the car.
 Angela testified that after the defendant left the house, Angela heard a noise coming from the basement. When she went to the basement to investigate, she saw that Weyrick was not dead. He had opened the lid of the freezer, and was attempting to climb out. She went upstairs, where she got a hammer and a kitchen knife. She hit Weyrick on the head three or four times with the hammer and stabbed him several times in the neck, chest, and abdomen with the knife. Angela then asked Gaston to sit on the freezer lid while she tied the freezer's handle with telephone cord. She told the police that she waited about three hours until Weyrick stopped breathing. When the defendant returned to the home, he and Angela buried Weyrick's body in the back yard.
 Lane told the police that she had last seen Weyrick with the defendant in Weyrick's car. When the police initially questioned the defendant about Weyrick's disappearance, the defendant denied any involvement. When the police questioned the defendant a second time, he gave his first confession, in which he stated that he had killed Weyrick in a garage at a different address than his home address.
 The police investigated the garage the defendant had described, where they found no evidence of a struggle. After the police confronted the defendant with the lack of evidence at the garage and with security photos of Angela withdrawing money from the ATM, the defendant gave his second confession. In his second confession, the defendant described burying Weyrick's body in the back yard. The police then went to the defendant's home, where they dug up Weyrick's body. The police also obtained blood evidence from various locations in the house that matched Weyrick's DNA. The blood evidence was admitted at trial.
 The coroner testified that Weyrick's body was recovered about a month after the murder and was beginning to decompose. Weyrick's brain was swollen, which indicated that it had been deprived of oxygen before he died. Weyrick's lungs were collapsed. Weyrick's body had multiple stab wounds to his back, neck, chest, and abdomen. Additionally, the body had multiple blunt force wounds to the head.
 The coroner stated that Weyrick died of the combination of bleeding from his multiple stab wounds, the blunt force wounds, and asphyxiation. According to the coroner, Weyrick could have died solely as a result of blood loss from a ...