Max had kids with a model Aki Hatada and they were married till 2016 but it was never public until earlier this year when she said somewhere they were divorced. They had two girls and a boy and she is raising them in Singapore apart from Max since 2013.
https://www.sponichi.co.jp/entertain...00044000c.html
There's too much that says the baby Ayu had was Pei's though.
Ayu's works maybe from now on will be Produced by ayumi hamasaki officially alongside Max?