craftgrrl | Sorry for the "What should I make for people you don't know?" post...

but I wanted some crafty people for help refining an idea!

My parents will be thirty years married on Friday week (aww). I'd like to make them something, but I'm a bit limited in scope. Restrictions:

I made them a collage for their 25th anniversary, and later found out that my dad isn't really into photos anyway, so photo-based presents are out.
They're quite practical-minded, so it needs to be either small or useful, and my abilities don't really let me make useful things.

Thirty years is the pearl anniversary, according to the internet, so it would be nice if I could incorporate that. One idea I have is based on a rhyme my mother used to use as a nicer version of "Be quiet and stop squabbling": "Birds in their little nest must all agree/ To live in peace and harmony." I thought of knitting two little birds and putting them in a nest with pearly beads for eggs. (I originally thought of having baby birds as well, but I'm child number four out of five, so I'd need to either make the nest big and awkward, or be made fun of for leaving people out.) Only things are:

I made this bird's-nest necklace for my mum for her birthday last year, so I'm not sure if it would look a little unoriginal and lazy (especially as she lost it pretty promptly, and I only gave her a replacement about two weeks ago. Now it's a brooch, for safe-keeping.)
I'm not sure whether to use the same tutorial as above - I really like how the necklace turned out, but I'm not sure if it would look a little messy made larger.

If you have any suggestions, or different ideas entirely, I'd be much obliged!