Just lost his sister

So, as the title says, my boy bunny just lost his sister that he has spent his whole life with. He's two and has never been without her. It was very sudden and he didn't get to say goodbye. I know that giving him lots of love and care is important now, but also giving him space to grieve. tough I really feel that a new mate would be best for him. You guys with experience of this, have did you approach this? New mate just days after or did you wait weeks? I just want the best for him but don't really know how to read the situation 🥺
And I also miss my sweet little voidbunny so much.. Thankful for any advice!