Sister deliberately giving her baby STDS

So being 33 weeks pregnant, setting boundaries like the no kissing the baby on the lips rule is pretty important to me. I was telling my mother that I was uncomfortable with my relatives (aunts) visiting my child as they posted a video of themselves kissing my sister’s 15 month old baby on directly her lips.

My mother said she was very bothered by other people kissing the baby too but my sister doesn’t think it’s an issue because she and her husband has herpes and they don’t mind their baby getting herpes together. Am I the only one thinking that’s just crazy stupid and ridiculous to set your kid up with stds???? And she’s supposed to be the most educated with her masters degree with law.

Edit: To clarify, my sister is also kissing her baby while having outbreaks, and allows visitors and relatives to kiss her baby on the lips. I just got to know about this today (baby is 15 months now) because I was having a conversation with my mother about it. But it has been going on long before.

I understand that the word std is offensive to some since it is a very common virus. “Technically, the CDC considers oral herpes an STD or STI (sexually transmitted infection), but that doesn't necessarily mean you got it through sexual contact. “ - https://www.webmd.com/a-to-z-guides/oral-herpes

Whether it is an std or not is debatable, but the point of this post is not to shame or make any one who have it feel bad. Rather, it is about whether as a parent, should she have tried to prevent it? And to not allow visitors to kiss her baby on the lips?