Hi, thank you for your question. Just a bit more information required to fully assist you:
-Are you in England or Wales?
-How old are the children?
-What are the terms of the court order?
Thank you for confirming. Grandparents do not have an automatic right to contact with their grandchildren, however, your son has a right to a relationship with his extended family. There is no minimum amount of time a grandparent has to see their grandchildren by law and this is dependant on the child's needs, contact with their parents and their wider day to day arrangements.
If you have any further questions regarding this please let me know. In the meantime if you found this information helpful please provide a positive rating using the stars at the top of this page. I will not be credited for answering your question without a positive rating. Thank you