EXPLAINED: Why is America targeting Putin's daughters in the midst of Russia Ukraine war?

Russian President Vladimir Putin's two daughters, Maria and Katerina, have become newest targets of US sanctions. US officials believe that the girls are hiding President Vladimir Putin's wealth.
According to the details of the US sanctions, Putin's daughter Katerina is a technology executive whose job is to support the Russian government and its defense industry. The second daughter, Maria Vladimirovna Vorontsova, leads government-funded programs that have received billions of dollars for genetics research from the Kremlin and are personally overseen by Putin.