Feeling selfish for TTC

SO and I decided today that we were ready to TTC. We want our baby girl to have a sibling because we both did and our brothers are our best friends, but the more I think of it the more selfish I feel. I’m scared I would be taking away from my first little love. Is this normal? Idk if I can do this to her 🤧 maybe I just have baby fever because my baby is turning one in a few weeks 😭💔