Why Grandparents are More Lenient Than Parents: Possible Explanations

There is often tension between parents and grandparents regarding how strictly small children should be disciplined. Grandparents are much more permissive of misbehavior and do not enforce the boundaries set by the parents. This often leads to resentment by the parents. The child is learning bad habits because the grandparent tolerates them, and the parent will be tasked with correcting the behavior later. Even excepting this, the child learns that the rules are different when the grandparents are around. (Perhaps it’s always worth pleading to other adults for a better deal when mom and dad are being big meanies?) The grandparents sometimes actively sow confusion and discord by protesting. (“Oh, it’s okay.” Or “Oh, just let him have it.”) This poisons the parents’ moral authority when they have to eventually lay down the law and enforce a rule. Finally, “Where the hell was all this permissiveness when I was a misbehaving little brat!?”

Possible explanations present themselves.

1. Different incentives. If the grandparent spoils the child, either by giving them too many presents or permitting too much misbehavior, they get all the benefits of spoiling the child with almost none of the costs. The parents will have to deal with the problem the next time the child, say, begs for a toy in the store or jumps on the couch. The grandparent gets a temporarily happy kid, while the parents have to deal with the petulant little monster this creates.
2. Mellowing out. Young parents are often stressed and not fully mature. A 60-year-old has more social intelligence than a 20-something or even a 30-something. So maybe younger parents really are too harsh and short-tempered and keep their children on too short a leash? Maybe if the parents mellowed out a little, they’d act more like their grandparents. And maybe if the grandparents could impart their full wisdom on their 20-something selves, they would have been more permissive, too.
3. Changing generational norms. Maybe the younger generation simply has stricter parenting norms than the previous generation? This is distinct from 2) because it is about how society as a whole changes over time, as opposed to how individuals change as they age. I find this one hard to believe, given that corporal punishment has been declining for decades (see Steven Pinker’s The Better Angels of Our Nature for a long treatment). I doubt if many grandparents suddenly pull out the paddle when the kid misbehaves.

Others?

Of course these explanations are not mutually exclusive. It could be some combination of all three. I put most of the weight on 1) because I have seen some particularly dunderheaded grandparental meddling, and done by grandparents who would certainly not have tolerated the child’s bad behavior from their own children. Also, I have seen where a grandparent suddenly become stricter when they have to deal with the child for an extended period of time. For example, when they take the child for a weekend. In this case, the cost of spoiling the child is "internalized"; the grandparent feels those costs, so they learn not to spoil quite so much. It was amazing to witness this lesson being learned. Something like, "Oh, now I see what you're dealing with!"

Still, there’s something to be said for 2). My gut says 3) should go in the other direction (making grandparents stricter than the parents). That said, I can imagine ways that the younger generation of parents are more constraining without being quite as authoritarian. We millennials are a generation of so-called “helicopter parents.” Maybe our parents and grandparents gave us more freedom to roam, but came down harder when news came back to them that we’d misbehaved. They had a “low surveillance, low probability-high severity” regime, compared to the opposite today. (Gary Becker would have approved.)