FWB with ex? PLEASE HELP??! OPINIONS?!

I dated my ex since we were very young and have been on and off with him ever since, for about 4 years, and everytime we go back to each other it's usually friends with benefits, but it also feels like were seeing each other. Last time, he ended up admitting he doesn't want to be just friends with benefits but is worried about dating me because our families don't like each other because we were so young when we dated. He said he doesn't think feelings like he has for me will ever actually go away. Now were back where we started again, friends with benefits and I don't know if I should just be honest and tell him I want more. We kiss and hold hands and cuddle, and he'll give me forehead kisses and bring up things we did when we were dating. What should I do? I'm nervous about what our families think as well but it's been four years and I don't see my feelings changing. Should I tell him how I feel, or just keep going along with FWB until someone cracks?!