In this task, you're given the title of a story consisting of five sentences, numbered 1 through 5. Your job is to determine which two sentences need to be swapped sentences in order to make a story that makes complete sense and is befittingly titled. Indicate your answer using the numbers of the two sentences in order, such as '34' or '25'. The first digit refers to the sentence which should come first in the story.
Q: Title: A Slight Modification in Nighttime Activity. Sentence 1: Snowball can still go out, but Clara keeps the door to the house shut. Sentence 2: Her cat, Snowball, is allowed out there until Clara's bedtime. Sentence 3: One night, Snowball caught a bat on the porch and brought it in. Sentence 4: Clara had to catch the bat with a net and set it free. Sentence 5: Clara's house has a screened-in porch in back.
A:
15