|This is a family comedy with Steve Martin, Bonnie Hunt, their dozen kids and the mayhem that ensues from having such a large family. Some of the mayhem derives from the 9-year-old son Mark's interest in herps. He has a pet bullfrog that causes trouble, and when he goes to a very large birthday party, he brings a birthday present that's a box labelled "Caution: Live Snake" and puts it on a stack of wrapped presents. He tells the woman taking the presents that it's a "Brazilian Mud Viper. She gets one live rat a week." When another young boy pulls out one of the wrapped presents below it, the snake box falls to the ground, opens up, and the snake escapes. This causes widespread panic. We see people running around terrified, screaming and yelling. But the loose snake is immediately forgotten about after Steve Martin explodes a bouncy castle, flies through the air and lands on the birthday boy, sending him to the hospital. Once again, a snake is the villian just for existing, but it's human-made toys and panic that cause the only damage.
I'm not sure what kind of snake was used to portray the Brazilian Mud Viper, but it reminds me of a white-sided morph of a bullsnake. I don't think there's any such thing as a Brazilian Mud Viper, but if it did exist, as a viper, it would be venomous and worth a little bit of panic at least.