Another person with the username u/Fabulous-Ad-5284 gave their perspective on the situation, as someone who is infertile.

“I wanted kids all my life, me and hubby tried for years, it will never happen. Trying almost killed me, so I had to choose: keep trying and die, or stop,” they said.

“I would have LOVED to help hold the flashcards for you!!! Hell, I would have gone full blown interpretative dance for you, if that is what it took to get it through their thick skulls that the wedding is gonna be childfree. It’s YOUR wedding, YOUR rules. NTA, at all.”

Source: https://www.buzzfeed.com/jenniferadams2/aita-brother-child-free-wedding