For all you moms crying at first day of school drop offs, I get it. If your child is taking it hard, I feel for you. It's pretty painful leaving your crying kid, but I'm here to tell you, the tears are only temporary.

My first-born recently started pre-k. While I witnessed other kids crying, my Nicholas stood strong, so I was left hiding my tears underneath sunglasses. However, that was not the case when he started preschool a few years back.

When Nicholas was two and a half, he started preschool – my heart, my soul and my BFF was starting a new chapter and I was dreading it. We were somewhat hesitant sending him three mornings a week, but my husband and I thought some social "non-mom time" would be beneficial for our somewhat cautious and super sweet son.

Day one's drop off was traumatizing. His teachers suggested I say a quick goodbye, and so I did — fighting back sobs. Nicholas was hysterical — crying and screaming "mama." My heart literally broke a million times.

But I listened to the seasoned teachers — two women I knew would look after, care for and console my crying toddler. I said a quick goodbye and left.

And then I did what any other mother would do: sit in my car in the preschool parking lot and cry in self-pity and guilt. I sat in the backseat alongside my second born, a baby, who needed my non-emotional attention. Sorry, second born, for being such a hot mess.

I sat there for a good hour, annoyingly texting the teachers making sure Nicholas was doing OK. Their response: he was fine. Timid, but fine. Quiet, but fine. "Observing from afar," but fine.

I gave myself permission to drive home.

A few hours later I picked him up. I walked into his classroom, and our eyes met. Reunited. He screamed "MAMA," as tears streamed down his eyes. My broken heart from earlier that day was full again.

Fast forward two weeks.

Two weeks later, after very hard drop offs, I walked Nicholas into his classroom. He carried his Darth Vader lunchbox with confidence, and led the way to his classroom with ease. All the kids were sitting on the floor doing some music activity, as I mentally prepped myself for his regular drop-off tears. But they never flowed.

Nicholas walked in, sat down, and started partaking in the music. And I stood in disbelief.

The teacher gave me the go-ahead nod to leave, so I shut the door and stood outside the classroom, peering through the window. He was smiling, and I started to cry.

He didn't even say goodbye to me.

A flurry of mixed emotions took over me. How could he not say goodbye? I'm his mama — the one he cried for. I'm his best friend. I rocked him to sleep every single solitary night for a good year. I still sit in his room when he goes to bed. I'm his everything — or so I thought.

My tears were bitter sweet. I was overjoyed seeing him happy, seeing him thrive, and seeing him progress from an "observer" to a "partaker." Watching him join the fun warmed my heart — made me proud, so very, very proud. My cautious, clingy child was finally feeling comfortable in his own skin. I saw confidence radiate as I peered through the window. My baby-turned toddler was becoming a little boy.

The preschool transition was tough. Real tough. But every day got easier. In no time, he began having fun — music, dancing, sports, art and more. Happiness is all I want for my children. With that being said, every day he's one day older. I'm sad and happy at the same time. We might be super-moms, but we can't stop time.

I grew up with a crying mother. She cried at everything — sad things and happy things. I swear, the woman was always crying, and still does to this day. As a child, I constantly wondered how she still managed to have tears left inside her. Hadn't she gone dry?

Well, I have since discovered the definition of mom tears. I suppose it's the heart's way of being so full, that it overflows.

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