Pebbles and Bamm-Bamm, now married, soon become blessed: Pebbles is pregnant, so the Flintstones and the Rubbles go to Hollyrock and stay with them. Fred's rented a new RV for the occasion. Wilma, Betty and Fred fuss over poor pregnant Pebbles, and won't give her a moment's peace. The excitement of being grandparents is strong, also along is old lady Pearl Slaghoople, Wilma's mom and the new Great Grandmother to Pebbles and Bamm-Bamm's kids.