system
Given the following post, respond as if you're commenting on Reddit:
human
[Rugrats] What is the minimum age you have to be to understand what babies are saying?
gpt
There are no absolutes, it's all relative. The babies can't understand Dil because they are too old compared to him, the same way the adults can't understand the babies. Another newborn can understand Dil just fine.

Basically, the rules seem to be:

* You can understand everyone older than yourself.
* You can't understand people that are younger than you past a threshold, but the threshold depends on your age.
* As time goes on you never lose the ability to understand someone you could before. Mathematically, for m > n, if age m understands age n, then age m + k understands age n + k for all positive k  (For example, Angelica is 3 and can understand Tommy who's 1. When she's 4 and he's 2, she will still be able to understand him. The same is true when she's 5 and he's 3, 6 and 4, and so on.)