Another Baby... Maybe?

My husband and I have a son (19m) and we have always openly discussed the idea of having another, and at one point the idea used to really excite him! His brother (and wife) are pregnant with their second baby AND his younger sister is pregnant with her second baby. Honestly, it's making me envious, so I opened a discussion with my husband to see what his thoughts were and now he says hes not sure about having another baby.

I love my husband, and his feelings about the subject are completely valid as to why he has doubts. We are at a point in our lives where we are transitioning. Hes in the military (will be 12 years at the end of this enlistment) and works for the post office. I'm currently a full-time graduate student with one year left before internship, I'm the primary caretaker for our son and I work a few hours a week to pay for my car. He isnt sure if he wants to reenlist but says if we have another baby, he will for sure so I can stay home with our kids longer. I dont want him to feel like he HAS to reenlist. If he wanted to, I would support him but I dont want it to be 6 years of him wishing he wasnt there.

This conversation brought up a lot more questions than answers and honestly, it's made me more confused about the subject of more kids. 😔 Has anyone else struggled with this topic and how did you get past it? TIA.