Dear Abby: Should I keep watching my son’s unruly dog?

Dear Abby: For the last four years, I have been hosting my son “Dennis,” his 6-year-old son, and his brother’s 8-year-old daughter every other weekend. Dennis bought a puppy, “Champ,” to go with his house and brings him on these visits. Champ is nice enough but extremely active. He runs wild, barks, digs holes, and has never been trained. The grandkids are cousins, and they are thick as thieves. They love running around indoors and out, but I am worn out.