Need to put my dog up for adoption

Ka

Needing to find a new home for my dog Jewels I love her so much and it really hurts to have to give her up. She is about 5 years old I got her when she was 6 months old she loves to run, escape out of the fence, and eat lol. We had our first son almost a year ago we want more children in the near future she has been territorial towards our son when he crawls next to her or to the baby gate where she is on the other side she snarls and snaps at him she has never bitten him but my husband and I don't want her to get to that point we cant just leave her outside and I have tried separating them it isn't working and like I said we would like more children in the future. She is German shepherd mix.