Legal advice needed for overnight access question

[SnoopyLovesYou]

My ex partner wishes to have the children overnight. I am against this due to certain concerns I have regarding his overnight care of them. It looks however as though the court is going to award him overnight in the near future as he seems to have convinced them with lies. I don't wish to say anything more here about this but if you are experienced in these matters I would be really grateful for a private message! Stressful times indeed and very little/ no support. Thank you.