I think it's likely Ioan suspects the visitation is being voice recorded for Alice to listen to on their return.
I think he just is getting tired of Alice calling Ella at 10.01am and getting a reaction from Ella. From his description, Ella instantly responds to Alice the moment they are apart which is not at all normal for any child, and very doubtfully happens any other time like if Ella goes out with friends.
It’s actually worse that those girls get up, have breakfast, get dressed, get in the car with him then immediately leave than not going at all, it’s so cruel of Alice to toy with them like this. It also doesn’t make any rational sense, they aren’t refusing to go if they get up and go with him initially, which exactly fits with them being scared once they leave home.
Them staying home and not going at all in January makes more sense, if they are detaching from him and the stress of it all is too much
and people have made comments that make it sound like Ella is acting autonomously, when she clearly isn’t.
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We all know what she’s told Ella as she’s told everyone else as well. She has now managed to convert her children into her conspiracy theory mentality
That he wants her to kill herself
That he’s trying to jail her
That they are setting her up online with trolls
That they are stalking Alice and tracking her
That they are tracking the girls and stealing information to use against her
That he’s hiding money and making them poor and homeless
That B has wrecked their lives for fun, on purpose
That daddy has a dark scary side
That daddy is a liar