My sister is overwhelmed and she wants to give up on being a mother?

My sister told me that her 10 month old son won't drink from a sippy cup, suck on his thumb instead of a pacifier and rather play with plastic bags and play with cardboard boxes instead of toys. She says she sees other babies holding their own bottle, sucking on pacifiers and sipping from sippy cups. Plus she also complain that her son won't nap when she wants him to (he fights sleep) and now wants to give my grandma her baby because she thinks she failed as a mother. My grandma has given birth to 11 kids and she's 85 and fighting cancer. Plus her baby's father is not around and she's overwhelmed. I told her not all babies the same and don't walk out on her son because he's not what you want him to be. What do you guys think?