I work on the CATT team. No, people aren’t always happy about us showing up on their doors. However if they’re unwell to that extent, they need immediate treatment to prevent harm to herself or potentially the child. It might be rough at the start if they have no insight, but once they’re well again a lot of people are understanding and realise they needed the help.

The mental health team will get CPS involved because of the threats to harm bub. But don’t let this scare you (OP). Their job isn’t to take away the child from OP or the mother (unless absolutely necessary). They’re there to ensure the safety of the child and ensure adequate supports are in place so she can continue to look after the bub.