Thawing the Widow

Catalina Gray is ten, has a genius IQ, a rather unhealthy coffee addiction, and is somewhat excellent at running away from her problems. Exhibit A: on the run from CPS after months of being under the legal guardianship of her abusive uncle. One day, she stumbles upon a strange hidden safehouse. A couple weeks later, she's living with the Black Widow and she has no idea why.