The fear motive you to focus on certain things to alleviate the anxiety caused by the fear.
Your daughter senses that fear/anxiety and wants to palliate the tension by telling you what she thinks you want to hear. In a child's mind, truth is a fuzzy concept. She just tells you what is convenient for the moment without being constrained by what did actually happen. So the testimony by a child is unreliable.
You may need to relax a bit. You don't have to be tense in order to be valuable. You're a good-enough mother your daughters are fortunate to have.
Fear is contagious.