Tina Simpson shared photos with Johnson and Ross from the celebration on Instagram, raising some eyebrows. She posted one picture of Johnson's head in her crotch while they both did the splits, and shared another of herself getting close to Ross.
Some social media users called the cozy snapshots "creepy," while others defended the family's "sense of humor." Jessica and Ashlee Simpson haven't posted from the vacation, but Ross did wish his mother-in-law a happy birthday and said they "are having the best trip ever!"
Tina Simpson is mom to Jessica and Ashlee Simpson with producer Joe Simpson, whom she was married to from 1978 to 2013. Tina Simpson announced her engagement to landscaper Jon Goldstein in June after two years of dating.
"He's a really nice guy," a source told Us Weekly of Goldstein at the time. "He's always cared about Tina. He's known them for 15 years and has been a part of their family. He's so happy she said yes! I know he had been planning on asking her for a while."
Jessica Simpson, meanwhile, married Johnson in July 2014. They share 3-year-old daughter Maxwell and 2-year-old son Ace.
Ashlee Simpson wed Ross in August 2014 and gave birth to their daughter Jagger in July.
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