Mike & Nicole’s OPP: Sean’s Mom Has Got it Goin’ On

Dear Mike and Nicole,

I have been best friends with my my buddy Sean since we were five. I moved away in high school and I am now 24 and recently moved back to Boise. I was really close with his whole family because we spent so much time at each others houses. A few weeks after I moved back to town I was invited to his mom's for one of their weekly family dinners. We all reminisced about our early years and I found out then that his parents got divorced about a year ago. Since that night, I've been texting and having lunches with Sean's mom and we've really hit it off. I'm sure it sounds weird, but she is just the type of woman I have been looking for. She knows what she wants and doesn't play games. Do I need to ask Sean for permission to date his mom? If he doesn't give us his blessing can we still date? Does it matter?