I recommend the filters if this is a big problem for you.   Then, as a responsible parent and grandparent, you can be selective in accordance with your personal tolerance, rather than restrict the artists in RR. 

However, this is an excellent opportunity for you to enrich your children and granchildren's lives by teaching them of the beauty of God's creation, the human body in its created form.  You have the ability to help them have a healthy attitude towards the body, rather than one that is filled with fear and shame.

I have one last suggestion if this is unsatisfactory to you.  Try to find a gallery that shows non-offensive art in accordance with your needs.  I am wondering if there are some religious galleries that would fit your limitations.  I mean no disrespect, I am only offering options to consider.  Segments of some faith communities have strict positions on nudity, therefore, they might appeal to you.

I hope this helps.  Best wishes...

Suzanne

“Music is harmony, harmony is perfection, perfection is our dream, and our dream is heaven”
Henri Frederic Amiel