Son has decided he doesn't want children

My son told me he's not having children... He's 21 and while I know its his choice and his reasons are good I'm still sad ill never have grandchildren. My son has mental.health issues. He can be very manipulative, vindictive, and he's a Narcissist. He hates children. He has said "Fuck them kids" several times. But he also sees himself being a very emotionally abusive parent. This is also the reason he doesn't have a girlfriend because he feels he will be an emotionally abusive partner. He's does attend therapy before anyone says anything. Just trying to get used to the idea of not having grand babies.

Edit: I'm not trying to put pressure on him. I respect decision. He thinks he will abusive because of the things I stated before. He's manipulative, vindictive, and a narcissist.