The new platform was launched this week, in an attempt to attract children who can't yet join the 'grown up' version of Facebook, which only allow users aged 13 or older.
In their announcement, the company explained that they decided to create the Messenger for Kids because of parents' concerns about letting their young children use other apps.
'Parents are increasingly allowing their children to use tablets and smartphones, but often have questions and concerns about how their kids use them and which apps are appropriate,' product manager for Messenger Kids Loren Cheng said.
'So when we heard about the need for better apps directly from parents during research and conversations with parents, we knew we needed to develop it alongside the people who were going to use it, as well as experts who could help guide our thinking.'
How does it work?Facebook are trying to ensure the app is safe for young children to use, so parental approval is required before kids are allowed to join.
Every time a child wants to add a new contact to their list, the friendship also has to be approved by a parent for each kid. After that child is on the approved contacts, they can live video chat, as well as send pictures and text to each other.
Children can also contact adults, who will receive the messages on their normal Facebook messenger app, but they too need to be approved by parents before they go in the approved contacts list.
A 'library of kid-appropriate and specially chosen GIFs, frames, stickers, masks and drawing tools lets them decorate content and express their personalities' will also be available for children using the app.
'Whether it's using video chat to talk to grandparents, staying in touch with cousins who live far away, or sending mum a decorated photo while she's working late to say hi, Messenger Kids opens up a new world of online communication to families', Facebook say on their announcement about the potential uses of the app.
Unlike in the normal version of Facebook, Messenger for Kids will not feature any adds, neither will the children's information be used for ads.
Who can use it?The new platform has been created for children who aren't allowed to use the original version of Facebook yet, which only allows users who are aged 13 or older.
Children will be able to video chat and send pictures and text to parent-approved contacts
Is Messenger for Kids safe for children to use?According to the BBC, Facebook's attempt at a safe app for children is receiving 'tentative support', with many thinking that since children seem to be using social networks anyway - it's estimated that over 20 million under-13-year-olds are on Facebook - you might as well point them towards one that offers more security.
However, issues regarding data collection still worry experts, who say that 'it is impossible to fully trust the platform' and to trust the fact that it's acting in the kids' 'best interest'.
'A messenger app for kids under 13 that only parents can sign them up for sounds like a nice idea on its face. But without clear policies about data collection, what happens to the content children post, and plans for the future, it is impossible to fully trust the platform', James Steyer, from US non-profit Common Sense Media said.
'We appreciate that for now, the product is ad-free and appears designed to put parents in control. But why should parents simply trust that Facebook is acting in the best interest of kids?'
Is it available in the UK?For now Messenger for Kids is only available in the US, and Facebook haven't revealed if they have plans to roll it out in the UK.
Would you let your children join Messenger for Kids? Let us know in the comments!