Future Uncle

My brother and sister-in-law took my father, mother, and me out to dinner and revealed that they were expecting.  Their child is due in August meaning my sister-in-law has been with child for a few months and my parents and I took to learning this differently:

Mom: I thought you had a bit of a glow about you.
Dad: I knew something was up when you said you’d stopped drinking.
Me: I noticed no changes in you that suggested that you were pregnant.
Sister-in-Law: Thank you, Terry.