I had a sim with the wish to get a tattoo, so I sent her to the parlor for one. She was 4 days away from aging up to adult, but after the tattoo, she was reset as if she was on her first day as a young adult. Meanwhile her husband is 15 days away from becoming an elder.
On one hand, I hate to force her to age up, but I also don't want to reset her husband. Bleh.