Putting pics on a camera memory card

I've been on holidays and my grandparents want to see the pictures as usual. Thing is I've already taken them off the cameras xd pic card, so the only copy I have is on the hdd. Is it ok to just drag the pictures back onto the card (or actually, another card, I don't know where the wire to connect my cam to the TV is, but I know where my mums is so I can put them on her cam). Will it break the card or will it be fine?

Cheers.

No, it'll work fine.

The only issue i can think of would be if your camera was much higher pixel count and yor mums camera struggled to view them. Even then, you aren't going to break anything, it might just think the file is corrupt or something.