I really wanna get married

We've been together for 6 and a half years, hes helped raise my 3 children from a previous partner and we also have a 6 month old baby together. Our relationship has been a mix of good, bad and tough at times. We've broke up a few times too, but we always find our way back to each other. We love each other unconditionally and we are ttc our 5th (his 2nd) and final baby. We've spoke about marriage before but it seems that the whole idea has been forgotten about because we've just settled into this life we currently live. We live together and have our little family, just no marriage and it's all I can think of lately. And I'm dying to bring up the subject but I don't want to sound pushy because I want him to be ready too, not just go along with it. But at the same time I think if I dont say anything then he might never have the urge to ask. Im not even bothered about the big flashy engagement ring or the way he does it, I'd be happy if he asked while in the middle of watching TV or having dinner. I just want the wedding and the marriage and the forever