Gift etiquette for LC sister?

Hey ladies! I'm working on my boundaries and this year went actively waaaaaaaay low contact with my sister. It's been tough and the guilt still hits me sometimes so I'm not always sure what the right move is.

I am currently 37weeks pregnant and she is 26weeks. I recently had a mini, Very COVID babyshower, which she attended after being invited by my grandmother. Sis sat on her phone in the corner the whole time, didn't even bring a card, and only talked about herself/her pregnancy. This selfishness is not surprising behavior and goes along with the multitude of reasons why I went LC with her.

The problem I have is that I'm not sure if I should still be the bigger person and give her a baby gift. As much as I can't stand my sister and am tired of giving to her without getting even a legitimate "Thank You" in return, I don't want to take that out on my neice. However, I also don't want to start feeling obligated/responsible to get my sister things for her daughter when my sister eventually cries poor to us.