I bow to no one in my utter and total contempt for Ted Cruz (with the notable exception of BoF who suffers with Cruz as one of his U.S. senators), but if we're going to go scorched earth on the children of every politician who thrusts them in the spotlight, we can eviscerate JFK and Jackie for shamelessly exploiting Carolyn and John Jr. and just work the list from there. That's a pretty wide swath we're cutting there.
Now if you're actively engaging the press or promoting mommy or daddy's politician aspirations the way Bristol Palin or Dante Di Blasio have, then they are opening themselves up to media scrutiny and satire as well. Such is not the case with the Cruz girls.
Children usually have no say how they are presented to the public by a politician who wants to show how much he or she is a family guy/gal. The press should not thrust microphones and cameras in their faces, ask them for their opinion on policy or controversial issues, dig through their background looking for dirt or follow them around peppering them with questions.
Kids are off-limits. Even Ted Cruz deserves that much.
Carolyn and John weren't, I don't think, used in the same way. They were quite small. I agree he used them w/re pics of the family and stuff but I don't think they were in campaign ads or the like. However, even if they were, it was a distinctly different time. Were JFK president now, I'm pretty sure the extent of his dalliances wouldn't go as uncommented-on as they did by the media of the period.
I also think there's a difference between posing for a photo, or having family at the convention, and putting the kids in actual ads in speaking roles in ads.
Chelsea Clinton existed, was on stage at the convention I think, but the public didn't hear her voice until she was an adult or near adult. I remember that being a thing, when she first spoke to the media, on, I think, a trip with her mother regarding women's rights someplace.
I don't know about comics calling her names. I know Rush Limbaugh was horrid and called her the WH dog or something idiotic, and was called out for it.
The Obama girls I've seen chided in right-wing media for things like wearing short skirts to the turkey pardoning or what have you. Some people are bananas. I think I've also seen legit comics using their appearances for gags, but directed at their father, like he's so boring they look at their phones.