The opening scenes at the amusement park is set in the 1960's, however a modern steel track coaster (painted red) is seen in several shots. Steel track coasters were not introduced until the mid 1970's and were not common until the 1980's.
At the amusement park, the mom is clearly in her 20s and the kids are approximately 8 and 10 years old. At the retirement home, the elderly mom celebrates her 75th birthday, yet the daughter is only in her mid-30s...she should be in her mid-50s.