Help IDing these Brown Dekay's snakes?

[0fast]

Found 3 of these under a rock near my house (eastern Canada). One got away but snagged these two:

i.imgur dot com / aJYslKi.jpg

(you'll have to fix the link, obviously)

The little one is about 5 inches/12cm long with the larger is roughly twice that. They're obviously Dekay's/Brown snakes but I'm wondering why such a size difference. The bigger seems to be an adult while the smaller might be a newborn, but a) according to what I googled Dekay's snakes usually give birth in around August-September, this is early May, which is usually their breeding period; and b) I've read there is some dimorphism with females being larger than males, but to this degree? And lastly while I have no idea how fast snakes grow, newborn Dekay snakes are usually like 7-8cm so it is at least a few weeks old?

Anyway just wondering if I happened upon an adult and its potential children, or a mating pair, or what. Thanks in advance for the help!

[FWK]

Good looking little critters. The little one is most likely last years baby, nearing its first birthday.