Life isn’t fair and neither kid will notice. I spent every Christmas with my cousins and I have no idea if I got more presents than them - hell I have no idea if I have more or less than my sister. Are you and your in laws matching up gifts for the kids as well? We brought 10 from mom and dad and 5 from Santa so make sure you do the same? Madness.

Do not take gifts from one set of grandparents to the other (and open them in front of another kid!). That's really poor form. Open them before you go, and your in laws should be able to understand why you did.

Open them before and take pics (can do it one night when he is already in pajamas). Then he can authentically say what he thought about them and you can send them pics of him opening / playing with them. No one needs to know that he did it two days early.

If there are 4 gifts, open 2 before you go. He can thank them Xmas morning for those 2, and you can explain that you saved the other 2 for when you got back home as something "extra special waiting for him".

It does not matter if they don't think your timing is perfect.

Open them at your home. Ask DS his preference on timing. No need to drag them to your parents, unless you know your nephew's parents are doing same (assuming he has other grandparents who provide gifts).

We are spending Christmas with my parents, out of town. My DS is 8, and my 11 yo nephew will also be there. My mom bought presents for the grandkids and they have roughly the same amount they will open. My In Laws shipped us a box with several presents today. They are traditional people and won't "get it" if DS opens them before we leave, and I am sure they will want a call xmas morning to hear how DS liked the presents. But if I bring them on the road with us to my mom's house, DS will have several more presents than nephew. Any ideas?