The Yahoo article was full of speculations and obviously has caused several on this thread to conclude things that just don't add up.
Nikolas Cruz has a younger brother Zachary. When their mother died they moved into the home of a family friend, Roxanne DesChamp. Roxanne knew the kids since they were very young. She was well aware of the behavior problems of Nikolas and the number of times the mother, Lynda, who was widowed had to call the police on Nikolas and by other accounts Zachary too. Lynda and the boys lived in a 600,000 home but before the mother died she sold it in a short sale meaning she got nothing for it but the bank retrieved a bit of their loss.
It sounds like their mother Lynda had a substantial life insurance policy. Some reports claim the money set up to be dispersed to the children in increments at different ages.
Nicolas started buying guns. Roxanne DesChamp wouldn't allow the guns in the house. She took the guns away from him and told him if he wanted to stay there, there would be no guns. According to DesChamp Nicolas became very angry and started tearing up her home when her son physically removed him from the home. She then called the police and told the dispatcher that she needed protection from Nicolas and that he was armed. That same night Nicolas phoned the police and said he had been beat up and kicked out of his home and told the police he had become angry when he couldn't find a picture of his mother. That's where the Snead's come into the picture. Their son was friends with Nicolas and they took him in and he did have a gun in his possession that they told him needed to be locked in the gun safe. The Snead's said he was very polite, followed the rules.
Zachery, Nicolas' younger brother stayed with DesChamp. After the massacre Zachery had a breakdown and the police were called and under the Baker's Act was forcefully removed from the home to a mental facility for treatment.
https://heavy.com/news/2018/02/zachary-cruz-nikolas-cruz-brother-rocxanne-deschamps-roxanne/
Broward school shooting: Brother to have mental health check
The reason DesChamp may have moved to take control of their inheritance is because Nicolas is incapacitated and so is Zachary at this time. I wouldn't be so quick to accuse this woman of sinister acts. There could be law suits filled now that it is known Nicolas has a big inheritance coming. She could be doing this to protect Zachery's inheritance.