OK me and my boyfriend are planning on getting married but I have a son that isn't his. I want to know if we get married and if something happens to me does he have any rights to see my son even though he's been in my sons life since he was just 4 months old?

Welcome to AMHD; no, a step father has no parental rights with respect to a step child.

No the step parent has no legal visitation or custody rights with the child.

The only right he would have is the right to fight for custody if you were to pass away. If you make a will be sure to spell that out. Being a step parent doesn't make it automatic anything.