Here are some additional things that gerbils don't do but kids do, that build your character into a mature adult:
1. Take their sisters' toys right out of their hands while they are playing for no good reason, then come and cry to you that the original toy keeper is mean and won't let them play with said toy.
2. As #1 is happening, a third child is crying that they need their butt wiped because they went poo.
3. As you are leaving to wipe butt of child in #2, the two in #1 break out in physical altercation and your puppy pees on the floor.
4. God willing - the phone ALWAYS rings at this moment. Doesn't the caller know : it is always a bad time? Call back in five years, please.
5. When asked to stop unrolling toilet paper everywhere, nicely, they ignore you.
6. When asked the same thing in #5 meanly, they fall apart "You are so mean, mommy! You hurt my feelings!" Then they run off with poo on their butt because you weren't fast enough to wipe it during your, um, conversation.
7. Refusing to go to time out.
8. Running away (and through dog pee) and hiding under furniture that is too small for you to get under when chasing them for time out.
9. Spilling your wine in the chase, and of course, breaking the glass.
10. Letting you know that from now on they will be very, very good if you would just give them chocolate and let them watch only one more My Little Pony!
11. (The switcharoo) Coming over and saying "I'm sawy!! I am your baby kangaroo! I waaav you!" and wrap there chubby hands around your neck, put their warm, wet, pudgy cheeks against your cheek, and sit in your lap.
See how sneaky that last one was? They are the ninjas of the emotion-switcharoo - one second you are so pissed off steam is coming out of your ears and the next you are chastising yourself for ever having an angry thought at your precious cherub. So, giddy up! Just because you can take care of a gerbil, does not mean you are equipped to take care of a child! (I wanted to clarify this given what I see day-to-day; it seems there really is confusion that the two are interchangeable).