Opinions? I have to act fast :(

My parents wants to take care of my first child forever and asked me to focus on my second child. I got pregnant with my first child when I was 20, I got married to the father after she turns 6 months old and I conceived another child within 3 months after marriage. My parents told me that I should focus on the "legally married" child and they want to take the full custody of my first child because they do not have a child together (My mom remarried, no child after more than 10 years) My mom really love my first child, I can really see that. She once told me that my first child reminds her of me when I was little. I am moving out in a few days, taking our house keys in 2 days time. They told me that I should leave my first child to them and bring my second child instead but my best friend told me not to because when the child grew up, she will be thinking that I didn't care about her or that I didn't want her. How? I love my children equally but I don't want to hurt anyone's feeling. Right now it's either they will be hurt if I declined the offer or I will end up getting hurt not to be able to have the bonding between a mother and daughter forever?