We can’t really say more without giving away a big, fat spoiler, but it turns out that:

Colin is a bit of a meddler, 

Hyacinth is more of a meddler, and: 

the only time all of the Bridgertons stop talking at once is when Penelope has something really embarrassing to say. 

Hey, we never said it was easy to marry a Bridgerton, just that it was fun...