Hi Serenity,
My kids are currently having all but 50/50 contact with their father. Every professional agency that has got involved have positively identified that he is emotionally abusing them and will continue to do so. This has been going on since we split early last year and is likely to carry on through court for a good part of this year before things change with his contact.
My mistake was to allow him a decent amount of contact that he had to agree to, but now we are stuck in the court system they have frozen this because nobody seems keen to make a decision despite the evidence against.
From my experience, I would suggest withdrawing contact and letting him fight for contact as suggested above, that way they will be safe with you throughout the process, not in danger of him harming them.
Good luck