Petal Sepal Confusion

How do plants keep petals and sepals separate? I found a trillium (Trillium ovatum) that doesn't.

This is a trillium, its three originally white petals fading pink in late spring. The petals rest on three pointed green sepals. Below the flower are three large photosynthetic organs, which I just learned are technically not leaves, but bracts!

And this is a trillium that looks to have merged its petals and sepals into one structure. Huh.

summertime begins

First thimbleberries (Rubus parviflorus) and osoberries (Oemleria cerasiformis) found ripe and eaten today + garden soil thirstily sucking down water = it's summer! 夏天！