Sibling Rights

my sister gave my brother verbal and a typed will but died without singing it. Her husband did not do what the request stated. so he died 8 months later. They had no childrens together, but he have 9 kids all are adults they was adults when they got married. She purchased a home with her husband as joint tenancy in California. My brother talked with the kids after their father funeral and told them what she wanted and they all knew this to. They was suppose to let my brother file a petition to put the property into his name and he would give them their father 1/2 share of the property appraisal value and keep the property the other 1/2 that she wanted him to have that was hers. She stated that everything should go to my brother. They had the property on the market before their father died but as of today it's of the market and have lots of tickets because of codes for the grass. The property taxes haven't been paid for 2 years . What can we do to get the property without it just sitting there and the value go down more ? They want talk with my brother, they said 2 years ago that they would get an attorney , which they cannot afford they couldn"t bury their father because one of the kids had spent all of the money on drugs before the father died . 89.000.00 dollars . furious