Saturday afternoon, I took the girls to a birthday party. It was lovely, very casual, and somewhat unstructured — a park, some hot dogs, a couple of crafts, good weather. The kids dispersed and mainly did their own thing. I tried to hold back from my typical hovering mode, and watched Sophie wander, trying to find her way.

No one else noticed, I’m guessing, but from my perspective it wasn’t good. Sophie was passive — head down, not talking, just sort of aimless and not really connecting with anyone – til finally she latched onto the dad of one of the party guests and had a grand time chatting with him until it was time to leave.

That was not out of the ordinary; I’ve grown accustomed to such birthday party behavior. But what happened next is new, and it’s thrown me for a loop. It’s made me think about the birthday party behavior in a new way.

Later that afternoon, I dropped Sophie at her BFF Sarah’s house for yet another playdate. These playdates have been extraordinarily successful! And I’m cautiously hopefully that they are not just pity parties; I think Sarah enjoys them as well.

But as we pulled away from Sarah’s house, I noticed a pattern has emerged. She doesn’t want the playdate to end. That manifests itself pretty normally — she and Sarah both argue, stall, beg. But once Sophie’s in the car, something happens that I haven’t seen.

She begins to sob. I don’t mean cry or whine or complain. I mean full-on, gut-wrenching My Heart is Broken and I May Never Recover sobbing.

This continues for the short drive home, and for some time after that. The reminder of future playdates helps, but not entirely. I hate seeing her so upset, but at the same time, my heart swells, knowing how much joy those times with Sarah bring to Sophie, particularly when they come with the freedom and novelty of playing at a friend’s house without mom.

It’s as though it’s so awesome, she can’t contain her emotions. She blows a fuse.

I wish we could hit a happy medium, where — like Annabelle  — Sophie hops out of the car at a birthday party, huddles with a group of friends, then leaves the party a little whiny but otherwise no worse for the wear.

That, like so many things, is clearly not to be. Not for now, anyway. And frankly, it leaves me weirded out. The short stature, the hole in the heart, the difficulty with handwriting — okay, I get it, those are results of that 21st chromosome.

But the more ephemeral stuff, like emotional thermostats? Weird. That’s the best way I can put it. Weird.

And there’s no handyman — or even a doctor — to call to fix it.

She’s had playdates before, sure. Good playdates, even — sweet little kids with well-meaning mothers. Kids who like Sophie, I know that.

But true friends? Real play? I haven’t been sure. Until Sarah.

Early in kindergarten — almost a year ago now — Ms. X started telling me about Sophie’s relationships. Several names came up, but none as often as Sarah’s. Sarah’s the youngest of several siblings, and towers over Sophie; Ms. X thought she liked playing caregiver. But Ms. X was always quick to point out that Sarah and Sophie really seemed to be striking up a friendship, too.

I guess so. At Sophie’s birthday party, I watched my kid settle into Sarah’s lap for a good hunk of time, and take her around to show her her toys. Sarah’s gift — Foofah, from Yo Gabba Gabba — was Sophie’s favorite.

And my favorite gift came toward the end of the party, when Sarah’s mom asked me if we could trade phone numbers. Sarah would love to have some play dates with Sophie over the summer, she said.

I practically swooned. I put the note with Sarah’s mom’s number up on the side of the fridge and stared at it for days. When I finally got up the nerve to call, I realized it was mid-June — and at the bottom of the note her mom had written, “We’ll be gone mid Juneish.”

So we waited. Every day, Sophie asked, “You call Sarah’s mom?” And every day I told her, “Soon! I promise.” Then it was time to go to the beach.

“When we get back, I promise!” I told Sophie. My phone rang as we were getting on the plane to come home. It was Ms. X calling to say she’d just run into Sarah and her mom. “Sarah’s mom lost your number, but she found it. She’s going to call for a playdate!” Ms. X promised.

I beat her to it. Friday morning I called. She called back almost immediately. We tried unsuccesfully to find a time over the weekend, and Sarah’s mom wound up inviting  Sophie to come over Monday afternoon (today). I had to explain that Sophie had never been to a playdate by herself. Could Sarah come over instead?

It was another sad working-mom-moment. Courtney oversaw the playdate. I texted her this afternoon.

How was playdate???

Good! she’s still here…got here around 230 and they were having so much fun I called to see if she could stay till 5 5:50

That makes my day!

They are pretty cute! And I talked to her mom about wed and we are going to go to pump it up in the morning

(Pump It Up is one of those bouncy places.) Sarah’s mom also agreed that the playdate was a big success. As for Sophie? She’s thrilled. She, Annabelle and Ray just got back from frozen yogurt (it’s quickly become a summer habit) and I couldn’t wait to ask her what she and Sarah did on their playdate.

She couldn’t wait to tell me.

“Me and Sarah sat on the Whoopee Cushion and I farted! And she farted!”

They also played hide and seek, she told me. Sophie hid in the bathtub.

Sounds like a great date to me.