Sister a lonely supporter of alleged killer Accused of murder: A court sketch of Gerard Baden-Clay. The sister of accused wife-killer Gerard Baden-Clay cut a forlorn, solitary figure at his court hearing this week. Her stoic and unwavering support was noticed but largely overshadowed by dozens of family, friends and friends of friends of the late Allison Baden-Clay. Curiously, she chose to inject her own family's grief into the public consciousness midway through the committal proceedings on Wednesday. "What has been overlooked by the media in this terrible tragedy is that Allison was my friend, she was my sister-in-law and I love her," Olivia Walton said. My family and I miss her and we grieve for her on a daily basis. Ms Walton believes her brother is innocent. "We implore the police to investigate every avenue so there's no miscarriage of justice in this case," she said. Mr Baden-Clay has been refused bail on charges of murdering his wife, as well as interfering with her body, which was found on the banks of a creek 10 days after she vanished in April last year. He told police the mother of three failed to return to their Brookfield home after going on a late-night walk, however, a slew of dramatic and sinister allegations emerged this week, including claims that Mr Baden-Clay was motivated by money and a desire to be with his mistress when he decided to kill his wife. Prosecutor Danny Boyle told the Brisbane Magistrates Court on Monday that Mr Baden-Clay was in financial trouble early last year and stood to gain about $975,000 from Allison's superannuation and death benefits. But Mr Baden-Clay was also having an affair and had promised his mistress he would be separated from Allison by July. "These two aspects of evidence alone or in combination circumstantially provide motive for the murder," Mr Boyle said. The evidence revealed Mr Baden-Clay's affair with colleague Toni McHugh had begun perhaps four years before Mrs Baden-Clay's death. One of his former business partners in the prestige real estate agency franchise Century 21 Westside, Jocelyn Frost, said she first became aware of the affair in 2008 and cited the not-so-covert relationship as "one of the main reasons" the partnership collapsed. Another partner, Phillip Broom, said it was sometimes "difficult to judge whether he was leaving his wife to be with Toni, or he was leaving Toni to be with his wife ... it was confusing to me as to whether or not they were in the throes of an affair, had cooled off in their affair or had rekindled their affair." Both conceded they had not parted ways on good terms but denied they were simply sinking the boot into the accused. In other evidence, Allison's battle with depression was aired but a forensic expert said levels of the antidepressant Zoloft found in her blood were in line with a therapeutic dose and were not high enough to cause her death. The expert also told the court he believed scratches on the defendant's face, which Mr Baden-Clay told police were caused by shaving, were caused by fingernails. However, he conceded they could have been caused by other abrasive objects such as coral, a chewed pencil or a broken stick. The hearing continues next week.