Book Title - read 2020ish, mystery, Detective, Part of a larger series. Spoiler.

[Rebe]

Looking for a Book about a detective inspector (Male) whose marriage is failing, he is working on a case where a little boy(?) is kidnapped in the middle on the night from their home. The detective visits a toy store run by the kidnapper either before of after this. The child is very posh and lives in a rich neighbourhood but there has been a string of similar incidents. In the end it turns out the man who Kidnapped the children is a schizophrenic who’s wife recently died and so was unmedicated, he was keeping the children above the toy shop and was told to by god and his wife who he was hallucinating.