So the other day, I heard a horrible scream come from my baby. You know the kind. The really bad kind.

I ran into the TV room, where my two girls had been sitting side by side, contentedly watching "Curious George."

The baby was hysterical and holding her hand.

I look at her wrist and see a deep imprint of teeth. It's so defined, a dentist would be impressed.

"Did you bite her?" I ask my toddler.

"She bit herself."

"Addie, tell me the truth. Did you bite her?"

I can see the wheels turning in her little head.

I know for sure the baby didn't bite herself. She is missing a front tooth, and the person who made this imprint definitely had all their teeth.

Addie: "Well, am I going to get in trouble if I tell you the truth?"

"Um, you're going to get in more trouble if you don't tell the truth."

She still won't fess up.

An hour later, the truth comes out. I send her to her room.

This is her first lie. Should I mark it down in her baby book?

It's pretty amazing how their little minds work, and how she knew she was going to get in trouble for what she did.

I wait until evening before I give the talk about why it's not good to lie or bite. Biting will get you kicked out of school! How would you like it if the baby bit you? It hurts! You have to always tell the truth.

I try quickly to think of all the good phrases I heard while I was growing up. Should I throw in the "liar, liar pants on fire" bit? Nope, too soon for that.

I'm not even sure she knows what the word "lie" means, but she definitely knows she made up a story so she wouldn't get in trouble.

So my friend tells me that when something like that happens, I can't punish her for the lying AND for the biting. I have to choose which is the most serious and go with that one.

These are the times I wish there was a parenting hot line where parents could call an 800 number and get immediate, helpful advice from a super nanny or pediatrician and not dumb remarks like, "Well, just bite her back."

Believe me, I've heard that one.

A few days later, it happens again — the biting and the lying. Apparently, they go together.

And as usual, my 20-month-old is the victim of the biting.

This time, Addie bit the baby's finger.

The baby screamed a painful scream.

Before I even asked, Addie offered this: "She just hurt herself!"

Me: "Then why is she holding her finger?"

Addie: "Well ..." (This is one of her favorite words, and she uses it to prolong something, like explaining why she shouldn't take a nap or why she didn't bite her sister.)

Me: "Tell me the truth. NOW!"

Addie: "Am I going to be in trouble?"

Here we go again.

Another time, she went under a table and colored on her legs with a marker, then emerged and told me Aubrey did it.

Never mind that Aubrey was in her crib napping.

I explained to her that there is no way her sister could have done that. She agreed finally that her sister played no part in the mischief.

I hope this isn't becoming a pattern. Isn't this what teenagers do? She's not even 4 yet.

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