This park just opened a few days ago at 18th and the Ben Franklin Parkway, directly across from the Basilica. It's a great park for families and everyone (though not a dog park at all). I recommend you take a look!

There's a spray-splash water feature, a little pond for sailing toy boats and a small ascending trail alongside a tiny stream that's essentially a model of the Wissahickon. There are little stools to sit on at the top of these rocks, and water sprays from the rocks every so often.

There's also a beautiful-looking cafe (looks like mid-century modern architecture that you'd find in a big national park) with WiFi and lots of outside tables. It's a Milk & Honey cafe. Good place to hang out with the kids for a while.

I believe the park was developed by a public-private partnership. Projects like this and Franklin Square Park remind me there are people in Philadelphia who know what they're doing.