Does anyone have experience with splitting royalties on digital streaming services

Like ITunes, Spotify, YouTube, ect. ?

My 14 yo has been making electronic music/beats for a couple years now and is collaborating with a rapper with a decent following on a single that will be released on all the streaming platforms and a video on YouTube. I’m sure this is nothing major and that no one will be getting rich (I’d be astonished if he makes more than a couple hundred bucks to be honest) but I’m very ignorant on all this stuff and just want to make sure we all know what to expect upfront so he isn’t let down and/or taken advantage of.

They are using distrokid.com to handle the monetization and distribution.

Any advice and guidance would be appreciated. Thanks!