I’m celebrating my 13th Father’s Day today. Yeah, hooray for me.

But what’s most significant about today is I’m the dad of a newly minted teenager.

My boy Eric is becoming a man and – much like it occurs in werewolf movies – the transformation is happening before my eyes.

He’s growing like a weed. He’s just 5 inches shorter than me and wears a size 11 shoe. In another six months he will be able to fit into my size 12s.

Eric reaching age 13 is more than a milestone. His metamorphosis is having an effect on the entire household.

He has his moods.

Sometimes he won’t speak for days. He rolls his eyes at my slightest action he deems uncool. Then, as if the moon had just turned full, he’ll give my wife, Julie, or me a big hug – in public, no less.

He doesn’t sit on furniture; he flops. The couch used to creak when he did this; now it groans.

His friends’ birthday parties once consisted of a dozen boys on a sugar high bouncing off of each other and hitting things – piñatas or baseballs at batting cages.

Dads increasingly making time to be involved with kids

Anderson: Wild times for dad of new teen

Goff: Father’s Day evokes memories of Dad

On the street: What are you doing for your dad on Father’s Day?

On the street: What is your favorite memory of your father?

Now, Eric gets party invitations from girls who dot their I’s with smiley faces.

There’s no roughhousing involved at these co-ed parties, at least as far as we hear, because he won’t tell us what goes on. The parents who play host to the parties tell us the boys stand in a circle and talk about baseball and the cars they want to drive in another three years, while the girls giggle and dance with each other.

Eric is paying more attention to hygiene, too. For a boy who used to have to be bribed to get into the shower, now we can’t get him out. Each morning, he sprays himself with half a can of Axe deodorant body spray. I prefer the scent of Brut from my teen days.

Our budding man has even let his hair grow to a shaggy 1970s length.

Overnight, he went from wearing T-shirts and jeans to donning only clothes that have an American Eagle or Aeropostale logo. He color coordinates neon purple and yellow knit polos with a rainbow of colored undershirts. He even has matching khaki shorts. We insist that he chip in to pay for this new wardrobe.

Julie and I have caught girls his age sneaking a peek at our dapper boy, not that he notices them, or lets on.

On Friday nights Eric likes to hang out at the ball field with his baseball buddies. He’s flexing the brief moments of freedom we’ve given him. His 9-year-old brother, Thomas, doesn’t like it, nor does he understand why his brother needs time away from the family. Then again, he isn’t 13.

Those freedoms will be tested in the coming five years, and even more so when he leaves the family pack.

In the meantime, we have a silver bullet for Eric’s independence, should he stray too far.

He still needs Julie to blow dry his wild mane.