What constitutes start of symptoms for 7 day self-isolation

[Yika]

Background: I have an EOW arrangement with my ex. This weekend is supposed to be his weekend. However, he had a dry cough and fever last week - fever Monday-Wednesday. He felt better on Thursday and went out, mixed with other people and did sport. Thus, he is not self-isolating. However I'd like to isolate my 9 year old DD from him during the 7-day period.

He is pushing me to send her straight away, because his other, older daughter has been there since Friday and he would like the two to be together.

Of course I would too, but I'm more concerned about respecting the 7-day isolation period. Should this begin from the moment he had a fever? (in which case I could send her from Monday - schools are closed here by the way) or should it begin at the first sign of symptoms (which he now says was the previous Friday).

Thank you.

I would say first sign of symptoms.

Arguably there is no need for him to self isolate. The advice to do so in case if a cough or fever came in on Thursday night, when he already felt better.

However, I don't think you're wrong for wanting to hold back contact for 24 hours, if you're worried. There will be plenty more disruption to contact over the coming months, I'm sure.