Are sickness bugs contagious before symptoms?

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Yesterday afternoon my daughter had a play date at her friends house. Today her friend is off school as she was vomiting all night. What are the chances my daughter will catch the bug?

They played inside for an hour and outside for an hour, she didn’t eat at the house. I’m clinging to the hope that it’s more contagious when symptoms begin and after, but they were playing together about 6 hours before symptoms began. Thanks.

Depends on what sort of bug.
We had a family/friends party, no-one was visibly ill at the party, that night 24 of us went down with Norovirus, we're not sure who "Patient Zero" was, tbh we were all too poorly to care, especially me who had family staying over and only one bathroom!
Good luck, hope dd avoids it