I need mommies opinions. I have a 2 and a half year old son. when we go places he likes to walk…

I need mommies opinions. I have a 2 and a half year old son. when we go places he likes to walk around but he gets tried so we use the stroller sometimes especially in the summer. we'll my little girl will be born in May and I can't decide if it's a good idea to get a double stroller so but kids can sit when we go out or just get a single for the baby. ? what did you guys do if you had two kids close in age.