Dad and son on relationship

Son: I will marry a good girl some day because I've been trying to be good. I've been staying away from any how girls.
Dad: that's good son...
Son: thank you dad. I've always pray for that.
Dad: come here son. I need to tell you this.The wife you will marry tomorrow is someone's girlfriend today. Am telling you this to stop anticipating on a good girl but plan to make good any girl you found as a wife tomorrow.
Son: Alright. Thank you sir...