C. Brachycephalus "The Child" Sling!

I just picked up my first sling named The Child 💕 isn't he/she so cute?? I tried feeding them a small feed (idk what theyre called but they came separately packed with The Child) but it was more angry with it than hungry lol. Based on the size of their abdomen though, looks like they can wait, right? Appreciate any and all advice!! 🥰