Rights of half siblings

My apologies for mis-understaing your earlier post.

In essence, are you saying that you want
your older children to have contact with your family along the lines that the court has ordered, and, that your reasons include the distress caused to your younger children by their conituned absence?

It would seem that you either try and negotiate agreement with the ex (perhaps through letters or mediaton) or if that failed seek enforcement of the order through the courts.

Appologies if i have muddied the waters again.