A neighbor said he is filled with guilt after hearing the cries of a 9-month-old boy who is believed to have starved to death in an apartment after his mother died of an apparent overdose . 'If I was closer to the noise , I would have done something . I did n't know . I feel so guilty . I feel so bad , ' William Gonzalez said . The brother of the Pittsburgh-area woman went to check on his sister Friday morning , when he found her and her child , Casey , dead in their second floor home . Sara Kessler , 22 , had not been heard from recently and may have died a week or two earlier , Assistant Allegheny County police Superintendent James Morton said . Scroll down for video . Sara Kessler ( pictured ) lived with her 9-month-old son Casey on the second floor of an apartment block in Millvale , Pennsylvania . They were found dead by her brother after he had n't heard from her for several days . She was found on her bed and her son was in the living room . The superintendent said there were no signs of foul play . Mr Gonzalez , who lives on the first floor , said he was most upset knowing that the child was left alone with no chance to survive . 'The thought of that little kid running around after she died ... looking for food ... It 's such a helpless feeling , ' he told the Pittsburgh Tribune Review . 'It 's a very sad situation in there , ' Morton told reporters outside the apartment in Millvale , just across the Allegheny River from Pittsburgh . 'It seems like he [ the infant ] tried to survive but there was no food or anything for him to have . ' 'It looked like he was trying to get around somehow by himself for who knows how long . ' Pediatrician Dr Stephen Nelson said that the child may have survived a week without water . Sara Kessler 's mother died of natural causes in the same apartment in November , Morton said . Gonalez and fellow tenant Elizabeth Freismuth said that the loss shook the young woman . Neighbor William Gonzalez said he feels guilty after hearing the cries of baby Casey following the death of his mother Sara ( pictured ) Kessler was known to be a drug addict by other residents of the building ( pictured ) and it is suspected that she died of an overdose . Casey 's body was found in the living room - he is thought to have starved to death . 'She seemed so sad her mom was gone . I told her if she needed anything to ask me , but she never did , ' Ms Freismuth said . 'Sara was a little on the wild side , but she was trying to be a good mother . She was devastated by my sister-in-law 's death , ' her aunt Kim Knaus said . Ms Freismuth added that Kessler 'loved that little baby . He was such a beautiful little boy ' . Police suspect Kessler died of a drug overdose , and needles were found all over the apartment . A former resident of the building told CBS Pittsburgh that she was a drug addict and said that her family had tried to get her help many times . No one else lives on the same floor of the apartment building . Autopsies were scheduled for Saturday to officially determine the causes of death . Three house cats were also found in the second floor apartment . Police say the animals survived because of an automatic feeder , according to WPXI . Kessler 's mother ( pictured with Casey ) had lived with her in the apartment until her death in November of natural causes .
Sara Kessler , 22 , and son Casey , 9 months , were found by Sara 's brother . Kessler died of a suspected drug overdose in apartment full of needles . A neighbor heard Casey 's cries for days , but they were unanswered . Kessler 's mother died of natural causes in the apartment in November . Three house cats survived due to an automatic feeder .