How is it having kids with a 3 year age gap?

I just found out I’m pregnant. And super nervous about the transition to 2 kids! My son will be three next month in June. When baby’s here in January, he’ll be 3 & a half years old. My question is, does anyone else have an age gap like this? I’m super anxious my son will give me a hard time with the baby. Please let me know how it is! I’m just looking for any kind of advice to ease my stress. Let me know in comments your experience and if it was easier with this age gap!

I have a 13 year old and an 8 year old and they get along great!