"If you had a most incredibly motivated parent, who was determined to get to the bottom of what was being collected before consenting, I'm not sure that they could get to the bottom of what's being done with the data", says Josh Golin, executive director of the CCFC.
Research into Amazon's Echo Dot Kids Edition, carried out by the Campaign for a Commercial-Free Childhood (CCFC) and the Institute for Public Representation (IPR) at Georgetown Law, found "blatant violations" of children's privacy laws and the illegal collection of their data.
A group of child protection and advocacy groups has filed a complaint with the Federal Trade Commission alleging the e-commerce giant's Echo Dot Kids - a voice-controlled computing device with parental controls - violates certain children's protection policies.
Amazon's website and literature directs parents trying to delete information collected about their child to the voice recording deletion page and fails to disclose that deleting voice recordings does not delete the underlying information.
"The FTC must hold Amazon accountable for blatantly violating children's privacy law and putting kids at risk". The nonprofit organization said its researchers were able to delete data from regular versions of Echo Dot and Alexa.
The Echo Dot Kids is the child version of Amazon's "home assistant" speaker device, which records and stores information from its users. But when the child asks what Alexa remembers, it still recalls that she's allergic to walnuts.
"Voice recognition technology and artificial intelligence tools such as the Echo Dot Kids Edition have the potential to enrich and educate kids, including through music and storytelling".
It's unclear whether the FTC will take up the complaint, since its investigations are rarely public.
In the letter to the FTC, the senators said Amazon's children privacy disclosure does not say how the device shares information.
That was the case earlier this week, when the agency issued a warning to a Ukrainian firm that its three dating apps appeared to violate COPPA because they were accessible to children.
But a draft of the complaint cites a number of alleged failings, including that the permissions need to be more specific and that the online portal lacks an effective system for verifying that a parent is the one providing approval for a child's use of the device.