Senator Elizabeth Warren, the top Democrat on the Senate Banking Committee, sent a letter Monday to Beast Industries CEO Jeff Housenbold and YouTube personality Jimmy Donaldson, better known as MrBeast, raising concerns about the company’s acquisition of Step. Step is a mobile banking app designed primarily for users under 18.

Warren’s letter focuses on Step’s prior involvement with digital assets. In 2022, Step partnered with Zero Hash to allow teens, with parental consent, to buy, sell, hold, and receive cryptocurrency and NFTs. The company later expanded that access to more than 50 digital…