While walking in the convent a priest passed one of the nuns and noticed she was gaining a little weight. "Gaining a little weight, are we Sister Angela?" he asked. "No, Father," Sister Angela said, "It's just a little gas."
A month or two later, the priest noticed that she had gained yet more weight. "Gaining some weight, are we Sister Angela?" asked the priest. "No, Father, just a little gas," she again replied.
A couple of months later, the priest noticed Sister Angela pushing a baby carriage through the convent. Approaching her, he leaned over, looked in the carriage and said, "My, what a cute little fart!"